Excursion to Paris: April 16th to 23rd, 1908

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  • 8 EXCURSION TO PARIS. various exposures of which had been seen on other occasions; but this time there was a section with plenty of fossils. The drive was continued through fine and delightful country to Pierre fond, where luncheon was served; after which the return journey was made to Cornpiegne by a different route to that followed on the outward journey, and this brought one of the most agreeable days of a most successful series to a close. Paris was reached somewhat after six, and packing and the paying of bills seemed to fully occupy the attention of most of the party for the rest of the evening. The next morning brought the general exodus and dispersal. EXCURSION TO PARIS. APRIL 16TH TO 23RD, 1908. (Rtp;rt by M. G. F. DOLLFUS.) APRIL 17TH.-AuVERS-SUR-OrSE. THE village of Auvers is built on the right side of the River Oise, on the declivity of a high terrace composed of a pretty good stone named Calcaire grassier. The con stitution of the hill can be easily studied in a quarry opened in a little dry valley on the south. On the level of th e Oise there are some glauconiferous sands somewhat difficult to observe, but in the rue Daubigny we have seen the sandy bottom beds of the Calcaire grassier and in places parts of this Calcaire grassier altered into a dolomitic brown rock, sometimes very soft. In the Poussain quarry a good section of the normal Caicaire grassier has been studied. The basement bed is a good lime- stone on the horizon of Cerithiun: (Camp anile) giganteum, the bottom bed of the middle Calcaire /irossler. Only a few parti cles of glauconite can be observed. The middle mass is constituted by a succession of calcareous beds generally full of miliola with a few casts of shells. This is a very good building-stone named by the workmen" Bane Royal." Near the second third of the excava- tion there is a great change in the nature of the limestone, it becomes much harder, finer, and the fossils are quite distinct; they are Potamides and estuarine fossils. These beds are, in our opinion, the bottom-beds of the upper Calcaire grossier, some- times named in books under the workman's appellation of "Caillasses." There is a long succession of thin beds, calcareous
  • EXCURSION TO PARIS. 9 and argillaceous, and alternations of hard and soft limestone, generally useless. It is at some distance behind the edge of the plateau that the sands of Auvers begin to appear. They rest immediately upon the Calcaire grassier, but we have been unable to see the contact at this point. It can be observed not very far away at Valmondois, and it is easy to see that the Calcaire grassier is deeply penetrated by the pebbly bottom-bed of the sands. The sands are fully exposed in two sand-pits both easy of access. This sand in some parts is turned into sandstone and is fullof fossils. It seems to be a sea-shore deposit, and little pebbles, broken shells FIG. 1.-POUSSAIN QUARRY IN THE Calcaire Lutrcie« AT AUVERS.-r;. F. Doll/us. (Reprinted by permission from Bull. Soc. Geol, de France, srd series, uol, xxuiii, 1900, p. '27.) and oblique stratification are characteristic. Nummulites variolaria is extremely abundant, and many corals give a good idea of the hot climate prevailing at the time. The occurrence of Nummulites uarioiaria, with a small propor- tion-about 5 per cent.-of Num. Heberti is very important, as the sudden invasion of these species in great numbers characterises the basement-bed of the Ledien in Belgium and the Upper Bracklesham Beds in England. We will return to this matter in the further discussion of the Parisian stages. The fossils of Auvers and Valmondois have been known for many years. They formed the subject of one of the first publications of Deshayes in 1824, and we gave a very full list of the shells in the guide to the excursion of the Geological Congress to Paris in 1900. With the
  • 10 EXCURSION TO PARIS. species living in the Upper Eocene times, much older species, derived from the Chalk or from the Lower Eocene beds, are frequently mixed. They occur as pebbles, and it is very important to put aside these species when we would make any conclusive comparison with other fauna. The number of species found in both the Sables Moyens and the Calcaire grassier is very considerable, and the early geologists such as Cuvier and Brongniart united both formations, but the stratigraphy is quite distinct, the composition and exten- sion of the two formations are distinct, and the establishment of a new Mage is fully justified, and I named it Auversien in 1880. The upper part of the "Sables Moyens" is concealed at Auvers, and is without fossils. Only three kilometres farther to the north, and thirty metres higher up, the succeeding formation, the Calcaire de St. Ouen, can be seen. SANNOIS. The visit to the hill of Sannois, which faces the hill of ArgenteuiJ, was favoured by very fine weather, and the view of the neighbourhood of Paris was very clear and extensive. Very large quarries are open at the foot of these hills for the extraction of gypsum to make the celebrated "plaster of Paris," and full stratigraphical determinations can be made easily. With the valuable assistance of M. G. Ramond, Assistant of
  • EXCURSION TO PARIS, II Geology in the Museum of Natural History in Paris, and of Mr. Leon Janet, M.P., Inspector of Mines, the succession of the various beds was explained, It is summarised in the follow- ing table. Unfortunately the works at the moment had not advanced as far as the lower marine mass with Phoiadomya ludenst"s. TABLE OF THE GYPSEOUS FORMATIONS. 3'00 0'60 18:> 0'75 7'00 1'50 Metres. 15 to 17rst Mas s of Gypsum or Upper Mass . ⢠. about This is the layer of Pa/~othe,ium, Anoplotherium, an d other mamm al iferou s bones described by Cuv ier a centur y ago-s-Saccharoid white mass. III. Marl with nodules. soa p-marl , with special flint s name d Silex Men ilite, ash gray (fossil; very scarce, but the same as th ose of the upper mass) abo ut 2'50 to 0'85 and Mass of Gypsum or Middle Gyp sum Ma ss, saccharoid with some stra tified beds more or less crystall ine (Rdeotherium), at the bottom various beds of marls about II. Marl, yellow, stra tified with very few fossils (Lucina in orna ta'[, some redd ish spots '. , Mar! grey, em ployed for cement, with als o a few fossils (Turri/ella zncer ta , Desh) interstratified with some thin beds of crys ta llised Gy psum. , . 3rd Mass of Gypsum, part of th e lower mass very cryst all ine, and with very numerous lay ers of crystal, na med ., Pied d'alouett es .. . about I , Marl s. yellow, named "Mastic " with P'loladomya ludens i s compact or stra tified . ⢠⢠⢠4th Mass of Gyp sum , not very constant and frequen tly absent , interb edded with marl s, yell ow and greenish, an d g-reat crystals of Gypsum nam ed "jers d~ lance " about In Argenteuil immediately beneath these lower marls we found the Sables d'Argen/euil or Sables de lIfarines, but in the north part of Paris they are partly replaced by a lacustrine limestone named Calcaire de N oisy-Ie-Sec, but its fauna is the same as that of the Calcaire of St. Ouen. It is very important to remark that although the mineralogy and stratigraphy are similar in all these beds, the palreontology leads to a very distinct classification, The fauna of the lower beds is always an Eocene fauna, and all relations of the shells of the marl with Pholadomya Ludensis are with those of Barton, Marines, and the Auverssands ; on the contrary, in the middle and upper mass of the gypsum the marine fossils disappear, and the continental fauna is an Oligocenic fauna with Pakzotherium. We have made a careful revision of the fauna of the Marne a Pholadomya from Montmartre, Gare du Nord, Argenteuil, and Ermont, and we think it is of general interest to publish it, as Deshayes and various authors have mentioned a mixture of Eocenic and Oligocenic fossils which, in fact, does not exist:
  • I Z E XCU RSION TO PARIS. FA UNA OF THE M A RNES A P HOLADOMYA L UDENSIS IN THE E NVI RONS OF PA R IS. Corbu/a pisum, SOW. Typ e a t Barton (C . mb -p':,um d'Orb ), Monne ville, Marine s. Le Rue il, Lu des, Headon H ill, Brocke nhur st, etc. Corbu/a pixidicu/a, Desh. Marines, Le Rueil, Monnevi lle, etc. (if. C. L am arcbi, Desh., at Bart on' . Corbu/a ficu s, Solander. Type a't Bar ton, Monnev ille, Ludes, Auvers, Essom mes, etc. PIw/adnmya ludmsis, Desh, Quon iam, Le R ueil, etc . (Two sp. MSS. from Barton, in Ed wards's Coll.) Psammobiol compressa, Sow. T ype at Barton , Brockenhurst, etc. (P. sfampmsis, Desh., pars). PsammoMa neg/ecta, Desh . Lud es. Eocen e Su perieur. Cardium /{ya'1u/osum, Lamck. Lu des, Le Rue il, Monneville. Lucina inornata ; Desh. Monne ville , on the top of the th ird mass of gypsum, Lucina elegans, Def, Ludes, Barton, Mar ines, Monnevi lle (l. Thierenst, Desh, pars). Lucl"a undulata, Larrick . (Diva1'zalla) type at Grignon. D iplorlonta Guyerdtti, Desh. 0 Ludes, Cultellus Prevosti, Desh. (Culldlus grlgo"im sis, Lamck. ?) Crassatella Desmaresti, Desh , Ludes, Chama squamosa, Selander. Type a t Barton, Le Rueil, Marin es, Ludes, Monneville. Cardita sulcata, Solander. Type at Barto n, Ludes, Monneville (C , Kicksi, in Desh. non Nyst ). Cardita Davidsoni , Desh. Marines, Le Ruc il, Monne ville ( incl. C. dtorrgens, Desh). Mytillls R 1f:tlu/ti, Desh . Mar ines, Le Ru eil (incl. M. Bioelzei, Desh) . A vicu/a D efrancei, Desh, Mon neville, Mortefontaine, et c. (,i. stampensis in Desh, pars) . N ucu/a bisu/cata, Sow. Type at Bar ton, Le Fayel ( N.ly d lia"a, Desh, (pa rs) non Bosq.). Ca{yptrtE~ aperta. Selander. Type at Bar ton, Lu des, etc. (Cary. striatriia , Desh, non N'yst ) , Turritd la dongat", Sow. T ype at Barton , Le R ueil, Quoniam ( 7. communis, Desh., non L. nee P hil.). IVa/ira paristrnsis; D 'Orb. N. d~pressa , Larrick. in Pezant, Mon neville i N. micromphalus , Desh, non Sand., Argenteui l ; N. mut" M/is, Solan tier non Lo, Bart on, Headen Hill, Hrockenhurst , Le Ru eil, Lu des, Marines, etc . Cerithillm tr ica r inatu m , La rnk, Le R ueil, Le Wouast, i\Ionneville, Ludes . (C. s./Jecu/alum, Edw ., Headen]. Ceruh,um Roiss)'i, Desh . Ludes, Mon neville, Sannois ( C. den/kulat14m. La mck in Pezan t) . Ceri/hium aoncauu m, Sow. Type at H eadon H ill, Monneville (C. pleurolo- moides; var . Auct.). Potamides moniliftrum , DeL In Monneville, Morrefontaine, H eaden H ill (c. perditu m. Bay. ; C. dtpez'difum, Desh. Mu1'ex defossus, Pi lk. sp. 1804. Ty pe at Barton, Auv ers , Monneville, Quo niam, Le Fayel (r 'usus sublamellosus, Desh. Voluta depauptrata, Sow. Ty pe at Barton, Valrnondois, MonneviIle, Brocken- hurst (inel. V. Fairi, Desh.) Psammocarcmus Hericarti, Desh , All the Bartonian and Mari nesian beds. Macz'opneustes Preoosti, Desor. We can deduce some very important teach ing from this list. The fauna of the marine beds of Paris with Pholadomya ludensis is exclusively Eocene, and closely related to the
  • EXCURSION TO PARIS. 13 Bartonian fauna. We have no doubt about its identity with the fauna of the limestone of Ludes, near Reims; and it is extremely close also to the fauna of Monneville, Le Rueil, Marines, Crenes, Quoniam, all these localities pertaining to the stage named Marinesien. It is not far from the revised fauna of Brockenhurst, and of the Marine beds included in the Headen Sa nds. ·,""~':.·;~··I Green ilIa rls. Wh ite lIlarls. Blue l\Iarls. Gyp s-um. F I G. 3.-S ECTION S HOWI NG T HE C ONTRAST B E- TWEEN T HE B EDS W IT H G YPSUM AND THE ST RATI - FIED B EDS. G RA NDE PLAT EA U D'ARGENTEUIL.- G. F. Dol!jtts. Series; the relations are the same with the Wemmelian and Aaschien of Belgium. But on the contrary our list is perfectly distinct from the species of the Tongrian of Belgium, as well as from the Hamstead Series. Immediately on the top of the great mass of Gypsum we observed a succession of num erous beds composed of marls, limestone and sands of various shades and different structure.
  • EXCURSION TO PARIS. The succession of these Upper Gypseous marls is summarised in the following table, in descending order. 9'75 r-so 5 "20 4'00 0 '60 0'20 080 Argile Verte, Marnes bleues d' Argenteui/. Marnes Manchu de Pantm, SaMes de Fontainebleau. Mantes fiu i/ld ees a Cyrenes de R omailwi/le, Me tres. 1 Sand , thi n, yell ow, pure , ex pands to 2. 2 0 (Wi th a bed of Ostrea cyathull' as basement bed) . { Marl, soft, yell ow, with very numerous cast s of fossils ; Cytherea incrassata, M " d, M< t t Cvth splmdida. CeritMum plieatum, o asse e on mar reo Pectuneulus, Natiea, etc. . . . Ca lcare ous Marl , full of Ostrea longlr. ostr is . ⢠" . ⢠. ⢠~. White greenish Marl with hard greyC 1 " .J B " Li mestone. . . . ..atcasre
  • EXCURSION TO PARIS. IS stead fauna appears. The following short list is absolutely characteristic: " Cyrena connexa (C. triata, Desh.) Striatel/a Nysti muricata semis- Nystia Duchasteli Cerz'thium jJlicatum Planorbis depressus The state of preservation of these species is not good at Sannois, but near Pont-Sainte-Maxence all these shells can be found, at the same horizon, in a perfect state of preservation, and in the same condition as at Vieux-jonc, in Belgium* APRIL I8TH.-ETAMPES. (With the valuable assistance of Prof. COURTY.) The members of the Association in company with a few friends arrived quite early in the morning at the station of Etrechy, and, taking a southern direction, they went up the course of the River La Juine. M. Courty drew attention to the large blocks of sandstone disposed in an oblique line across the valley. They are the remaining trace of a great and thick band of the sandstone of Fontainebleau crossing the valley at a very high level, and not yet dispersed by the flood of the river. It is very interesting to note that the Fontainebleau sandstone is not a continuous extended bed, but forms only bands two or three hundred metres wide, parallel, and very long, disposed from the N.W. to S.E. crossing the Paris basin from Evreux in Normandy to Sens in Burgundy. The gravel in the bottom of the valley of the Juine is important, and disposed in terraces at 5, 10, and 20 metres up the sides of the valley. Its thickness IS about 3 metres, and it is formed with calcareous pebbles from the Calcaire de Beauce, siliceous flints from the Sables de Fontainebleau, and granitic sand from the Sables de la Sologne. In our first sand-pit at Jeur we saw a very fossiliferous bed belonging to the lower part of the Sables de Fontainebleau. The sand is white or yellow, without stratification. FAUNA FROM JEUR. Natz'ca crassatina Bayania semidecussata Rissoia turbinata Potamides Vivarroi (elegans) Cerithium plicatum Pedunculus obovatus " angusticostatus Meretrix incrassata " splendida Ostrea cyathula. ⢠G. Dollfus et Vasseur, .. Coupe Geologique du Chemin-de-Fer de Mery-sur-Oise," Bull. Soc Geol., T. v, p, 243, 1878; G. Dollfus, "Notice sur un nouvelle carte geologique des environs de Paris," Berlin 1900, 124pp., cartes; Dollot et Ramond, " Les grandes platrieres d'ArgenteuiI," Mem. Soc. Geol, France, Iv, No. I, 48 pp., 4 pl. 1905.
  • 16 EXCURSION TO PARIS. MORIGNY, Cardium Defrance:" " scooinuia Luana Thierensi " H ebertz' Bz'ttz'um sublima Bithz'nella helicella " Duouissom Voluta Rathz'eri Cassidaria Frissoni Pleurotoma belgz'ca Crossing the valley, we went on the right side to Morigny. Another sandpit in this place showed another horizon of the Sables de Fontainebleau a little higher up than the sands of jeur. The 5 __/~f,;-~:)J.:~:;;'::i~~~ti~iJ1~{;XoF::.p~4 ' \U' y :..::.: .... ::.. ::.~:.::.: : .. . s . . ,' "'""-----r'~: :·"-':: -:EZ:~~ · · FIG. 4.-SAND-PIT AT JEUR.-G. F. Dolifus. fauna is not very different, but more varied. The quarry, unfortunately abandoned for years, is much overgrown, and does not allow the stratification to be seen, but some little holes always provide fossils. FAUNA FROM Buccin u m (Comz'nella) Gossardz' Potamides conjunctus " trochleare Cerir/uu»: B oblayi iVatiea erassatz'n~ Rissoa turoinata " dubia " inchoata Ch enopus speciosus Lampusia jlandrz'ca We lunched at Etampes about one o'clock, and immedi- ately after proceeded to follow in the same valley the succession of the other horizons of the Sables de Fontainebieau, The upper part and main part, sometimes in the condition of hard sandstone, is generally without any fossils, but the top part at the contact of the lacustrine limestone of Beauce is fossiliferous in the south direction; it is named horizon of Ormoy, The list contains the most characteristic species of the sands of Fontainebleau, but there are a few more new species all peculiar to the Oligocene. Not one occurs in the Miocene, and there is a very great break between the upper Oligocene beds of the Paris Basin and the lower Miocene beds of the Touraine Basin.
  • EXCURSION TO PARIS, 17 FAUNA Natica crassatina Potamides Lamarck: Cen'thium plicatum Murex conspicuus Ostrea cyathula, var. Corbulomya triangula FROM ORMOY. Cardita Bazin:" Lucina undulata Avicula stampensis Bithinella helicella " Dubuisson:" Sfmothyra pupa. We visited the Faubourg St. Pierre, near Etampes, to see the contact of the lacustrine limestone of the Beauce with the Sables de Fontainebleau. On the top the sands take a violet shade, and pass into a lignitic black bed not very thick and local, and are capped by a calcareous white marl with black flints and full of Potamides Lamarclsi. A little above, the first beds of the limestone of Beauce, appear charged with Cyclostoma antiquum and various species of Lymnea. It is very difficult to draw a limit in this FIG. 5.-SECTION ON THE ROAD TO THE CEMETERY OF ST. MARTIN, ETAMPES.-G. F. Doll/us. succession, and the Sables de Fontainebleau are in very intimate connection with the lower limestone of Beauce, better called Calcaire d'EtamjJes. Near the old church of St. Martin d'Etampes M. Courty showed us an old Pleistocene tufa, with plants, studied 150 years ago by Guettard under the name of Osteocol/e. It was believed to be specially favourable to cure broken bones. In the valley of the Chalouette the sandstone is quarried over an extended area; the surface is deeply undulated, and the contact with the lower marls of Beauce can be easily studied. At the end of the excursion we saw on the road from the cemetery of St. Martin to the plateau, in a section of limestone of Beauce, a large pipe or natural hole full of a granitic sand much kaolinised, a very curious outlier of the sands of the Sologne and the Orleanais. This formation must be classed with the Burdigalien, and at that time a great stream coming from the central plateau of France, running by the high valley of the Loire and of the Allier, spread in the south and western parts of the Paris Basin, falling into the sea in the environs of Havre in the Channel, where similar granitic sands are known on the top of the high Cretaceous cliffs. PROC. GEOL. Assoc., VOL. XXI, PART I, Igog.J 2
  • 18 EXCURSION TO PARIS. There was not time to look at the occurrence on the top of the hill, of a hard blue limestone full of fossils, Limnea pachygaster, Planorbis solidus, marking the presence of the Calcaire de I'Orieanais, overlapping the Caicaire d'Etampfs, and classified in the true Aquitanien. This limestone is also penetrated by the granitic sand. APRIL 20TH.-CHAUMONT, MONTJAVOULT, AND GISORS. (With the valuable assistance of M. CHEDEVILLE, Ingenieur of the Western Railway Company) . Immediately on the arrival at Chaumont-en-Vexin, we saw in a wood near the station a little excavation made by the kindness of M. Chedeville, showing a blue or brown plastic clay full of Ostrea bellovacensis, belonging to the stage of Lignites of the soissonnais, the lowest of the formations accessible in the environs. Close to, and a little higher up there is a sand pit where we found a yellow argillaceous sand, somewhat glauconi- ferous, with hard nodules named" Tetes de chat." These sands belong to the "Sables de Cuise," but here they are much altered and without any fossils. In another quarry at a little higher level, we saw the Lower Caicaire grassier, a sandy glauconiferous limestone, full of fossils. The section is very good, and on the upper part is a bed characterised by Cerithium (Campanile) giganteum, marking the bottom bed of the middle Calcaire grassier. In another pit we have been able to see the contact between the Sables de Cuise and the Calcaire grassier. It is important to notice at this place the trace of an important denudation with pebbles, rolled fossils, teeth of squales, corals, and .Nummulites lcevigatus. This bed is always full also of glauconite. All the pari sh of Chaumont is covered with excavations more Or less important, open in the Cakaire grassier and very fossiliferous. On the table of the Plateau, and specially near the village of Chambord the upper Calcaire grassier is largely exposed. It is a white rough limestone full of Natica parisiensis, Dissostoma mumia, Lucina saxorum, Potamides lapidum, P. cristatum, and Cen'thium thiara. On our way from Chaumont to Montjavoult we crossed a very fine country by Reilly, Delincourt, Beaugrenier, cut by deep ravines open in the thickness of the Calcaire grassier and the lower part of the Sables Moyens, and near the village of Le Fayel, at 3 kilometres on the edge of the great road from Paris to Dieppe, a very celebrated section full of fossils similar to those of Auvers is always open. Approaching the foot of the hill of Montjavoult we visited a very important little quarry giving the composition of the upper part of the Sables Moyens, and the contact with the lower part of the Gypsum stage, the section was fully explained by Mr. Pezant, geologist and arti st inhabitant
  • EXCURSION TO PARIS. of Montjavoult. He gives us full information about the critical fossils found at this point, and his list (see page 20) is new, and presents a special interest. SECTION OF THE QUARRY OF LE WOUAST, NEAR MONTJAVOULT. Metres. 9. Grey or greenish Marls, compact (belonging to Gypsum). .s. Calcareous coloured marl or limestone. (c) Hard bed with Dissostoma mumia, Nystia microstoma (Calcaire du Itouast). 0'30 (b) Soft bed, white ⢠⢠0'10 (a) Hard Marl, white. ⢠. .. ., 0'45 7, Irregular, sandy, little hard, with Helix Menardi, and Bithinella 0'08 -6 Calcareous Marl or Limestone. (d) Very hard and yellowish ⢠0'12 (c) White Marl ⢠⢠⢠0'04 (b) Hard yellow Limestone ⢠0 30 (a) Grey stratified Limestone. , , ⢠⢠⢠⢠0'16 .5. White, soft Marl, but little fossiliferous: Lymnea longiscata,L.pyra- midalis, Planorbis goniobasis, Hyd,-obia pyramIdalis (Calcaire du Bois du Mulot et de Noisy-Ie-Sec) ⢠0 20 4. (d) Yellowish hard Limestone 018 (c) White greenish Marl, ⢠, 0 30 (b) White Marl, with yellow points. 0 10 (a) Grey hard Marl . . , , . . . . 030 .3. Stratified sandy Marl, greenish or yellowish, with Corbula minuta 0'66 2. Hard sandy Marl, with good many fossils (Wouast fauna) , , 0'25 I. White or violet sand, without fossils, very thick (Sables de Marines). The correlation of these beds with those of the environs of Paris is not yet perfectly conclusive. NO.9. These marls belong very likely to the upper mass of Gypsum. No. 8'7. Take probably the place of the third mass of Gypsum. The fauna is always Eocenic. No.6. These various beds are Eocenic, rather hard, and are probably on the level of the Marnes a Pholadomya ludensis; the mineralogical aspect is very similar but harder. No fossils occur. NO.5, This lacustrine bed is very extensive, and is placed between the Sables de Marines and the Marnes a Pholadomya. The fauna is the same as that of the Calcaire de St, Ouen, No. 4-3. Marls and Limestones, until at present not conclusively classified. (Fourth mass of Gypsum?) NO.2. This very fine fauna, nearly approaching that of Barton, characterises the upper part of the Sables of Marines No. I. No important sub-division; no etage can be established between these various beds; the fauna follows always the same line without any change, and the lower lacustrine fauna reappears when the fresh water conditions retake the place up to the fluvio-marine invasion,
  • 20 EXCURSION TO PARIS. LIST OF THE FOSSILS OF THE QUARRY OF THE WONAST, NEAR MONTJAVOULT. (Basement Bed.) Odontostomia mediana, Desh. = O. nisoides, Coss. Adeorb,s politus, Coss, Phasianel/a Lamareki, Desh, " arenularia , Casso lJelplzinula dejecta, Pezant = D, turbi- noides, Desh. non Larnk. Siphonodentat'''m parlsiense, Desh, Chiton Bouryi, Rochebrune, Anomia psammotheis, Bayan, Avicula transversa, Desh, Perna Lamarcki, Desh. Modiola ambigua, Desh. A rcoperna capil/aris, Desh. = A. Sear- lesi, Chelot, Modiolaria arenularia, de Raine et Munier. . Area capillacea, Desh. Pedunculus nuculalus, Lamk. Nueula mtnor; Desh. Venerirardia suleata, Sol. (Cardita). Crassatella trigonata, Larnk, II sutcata, Sol. Lutetia drficiens; Coss, Erycina ruellensis, Cess. Laubriereia cvcioides, Coss. Cardium granulojUm. Lamk, Chama turgidula, Lamk. Psammobia compressa, Sow. " Baudoni, Desh. " papyracea, Desh. Herouvalia minima, Desh, Cultellus grigonzensls, Desh, Sphmnia Passyi, Desh, Sphmnza resecta, Coss . II mqu,lalez ahs, Desh. Cardiiia Michelini, Desh, Corbula minuta, Desh. lJ1arlesia aperta, Desh. Lucina gibbosula, Lamk. .5,) ndesmya exiiis, Desh II drltoidea, Desh, II brevis, Desh. Clavagella coronata, Desh, A. PEZANT. On the way up to the top of the hill of Montjavoult we saw a very important greenish argillaceous bed belonging to the Upper Marls of the Gypsum, and the horizon of Ostrea cyathula is very well shown near by. Immediately afterwards we saw a thick mass (at least thirty metres) of yellow sand, easily recognisable as Sables de Fontainebleau, near the old church built on the summit of the place previously occupied by a very old temple to Jupiter (Mons-Jovis). We encountered some blocks of a hard Helix Menardi, Brong. = H. monilis, Desh, Limnea longiscata, Brong, II pstUdopyram,dalis, G. D. II crassula, Desh, Scaphander Brongniarti, Desh, Bullinella conulus, Desh, II denudata, Desh, Oliva Laumonti, Lamk. A ncillaria obesula, Desh. Margz1ulla bifidophcata, Charlesw Mitra puellina, Lamk. = M. parva, Edw, = M. vincenti, Cess, Liostoma bulbus, Sol. Fusus sublamellosus, Desh, = Murex depauperatus, Desh. Cerithium thiara, Lamk, = C. thia- rella, Desh. Cenihium tricarinatum, Lamk. (num. var.). Cerithium moniliferum, Defs, in Desh, = C. deperditum, C. perduum, C. obscurum, C. contabulatum, Cerithium pleurotomo,des, Lamk = C. concavum, De.h. Vermetus cristatus, Desh, Melania lactea, Brong. Bayania hordeola, Larnk. = Mel. delibala, Desh. Paryphostoma turrtcula, Brong. Lacuna micromohalus, Morelet, Rissoia nana, Lamk. II Barren, Mor. Hydrobia p'yram,dahs, Brard, sp. Stenothyra mediana, Desh, = S. cu- neata, Coss. â¢/lI)'slia microstoma, Desh. Cyciosioma (Megdlosloma) mumia, Lamk, Bouryia conoexiuscula, Coss. Capulus squamaformis, Lamk, Ca~yplra aperta, Sol. Plesiothyreus parmophoroides, Coss. Ampuilina depressa, Lamk. = Nalica pariszensis, N. studert.
  • EXCURSION TO PARIS. 21 siliceous stone named "Meuliere," sometimes fossiliferous, and known as Meuliere de lIEontmorency, being an altered aspect of the lower part of the Calcaire de Beauce, The view from the top of the hill of Montjavoult is of great interest. In the north the ground rises slowly, and marks the ascending slope of the anticlinal of the Pays-de-Bray. discovering a great extent of land. In the east many hills and forest, with fields in great variety, extend over the central Tertiary part of the Basin. In the south the view ends far away with a line of hills on the left side of the Seine, and in the western direction a large plateau of chalk suggests the approach towards Normandy. After luncheon, going to Gisors, the time did not permit a stop for studying the Sables Mo)'ens and Calcaire grassier in the northern direction, but at the Mont de Magny we stopped to see a very fine sandpit open in the Sables de Cuise, where a good many fossils have been discovered, and some sandstones are full of Nummulites planula/us and Alveolina eiongata. The junction with the Calcaire grassier is well exposed in the highest part, and fossils of that formation have been obtained also in good condition. On the road a few metres lower than the last beds of the sand pit, we saw a spring and watering place on the level of the plasti c clay with Ostreabellouacensis, similar to the bed already seen at the beginning of the excursion. The White Chalk, with black flints of the Upper Senoni en, can be observed immediately below, some hundred metres distant. The excursionist s should also have a very good recollection of the old Gothic chur ch of Gisors, and of the old and extensive castle commanding the town. A PR IL Zr.-G RIGNON. We arrived at Plai sirs Stat ion at 9.30, and gained Grignon on foot. In the course of our walk we crossed a dry chalk valley, where we saw a well in course of sinking. At the time it was 65 metres deep, without a drop of water. This is a new and good example of the irregular circulation of water in Chalk, this Chalk, with a few black flints , belonging to the upper part of the Senonien, and with fragments of Echinocorys ova/us, being entirely dry. Along the road we saw the basement-bed of the Calcaire grassier close to the Chalk without any intermediate bed. The best sections are in the park of the old castle of Grignon ; it is now an agricultural college of good reputation, and we visited the laboratories, collections, and stables. The renown of the Grignon fossils is very old, and Bernard- Palissy, the celebrated artist in pottery, figured on his dishes many fossils from Grignon which are quite recognisable. I have been able to give the names to some of these reproductions of the "Rustic Figurines" now in the Louvre collections: Cardium porulosum, Voluta spinosa, Turritella imbricata, Fusus !ongtevus,
  • 22 EXCURSION TO PARIS. Natica parisiensis, Chama, Ancillaria, etc. Since that time Guettard, Bruguiere, Lamarck, Defrance and Deshayes have collected in Grignon, and most of our most typical Eocenic species came from this locality. More recently Calliat, Lousteau, Besancon, Bonnet, and Cossmaun have perfected the lists from these quarries, bringing up always new species. The number of different forms is not less than 800 species. In an excavation, about 7 metres deep, made especially for the researches of geologists, we saw a soft, nearly white, sandy limestone full of fossils splendidly preserved. The bottom bed is a little glauconiferous, and some fossils are particularly so, the main mass, a little yellow, is full of foraminifera, as Orbitolites complanata, Fabulan"a discolites, Alveolina Bosci, and mollusc shells are con- fusedly accumulated in a thick bed. The upper part of the section is whiter and a little harder. Some special species, as Cardium aviculare, Lucina concentrica, Modiola sub-carinata are characteristic of the upper part of the middle Calcaire grassier. Generally it is impossible to see any section lower, but just at the time of our visit, various works, made to obtain water, permitted us to examine the lower beds. We found that the lower part of the Calcaire grassier was a glauconitic sand in direct contact with a plastic clay, blue, red or black, without fossils, impermeable and about 4 metres thick, the chalk coming in at the bottom of the valley. Another series of excavations on the right side of the Ru de GaIly show that the White Chalk with black flints, rise up to 6 or 8 metres above the bottom. This chalk is covered by a thin bed of "clay with flints," passing to a plastic clay, yellowish, five metres thick, and covered by the sandy and pebbly basement-bed of the Calcaire grassier with corals, teeth of squales, broken shells, etc. The most characteristic species are: Ostrea ftabellula, Venericardia planicosta, Cardium porulosum, Chama calcarata, Pedunculus pulvinatus, Eupsammia trochijormis, Sphenotrochus crispus, Lenita patel/aris, Echinantus Cuoieri; Echinolompas affinis. At the west end of the park of Grignon, near the Thiverval Gate, is an old quarry showing the lower part of the Calcaire grassier. The limestone beds are more or less hard and glauconitic, this part is about 4 metres thick; the upper part of the section is occupied by the zone with Cerifhium giganteum, considered by us as the basement bed of the middle part of the Calcaire grassier. In Thiverval the beds become much harder and thicker, and cellars are excavated in that formation. There is no appearance of Sables de Cuise in the district, and the Lignites du Soissonnais have greatly thinned even when present. All the shales dip gently to the north, and gain in thickness in the same direction. We were not able to examine the Upper Calcaire grossier on the plateau. All excavations are now entirely closed.
  • EXCURSION TO PARIS. 23 3'30 1'50 0'60 1'80 3'50 0'80 2'00 APRIL 23RD-COMPIEGNK AND CUISE-LA-MoTTE. Our excursion was, at this stage, unfortunately a little inter- rupted by bad weather. We crossed the central part of the Forest of Compiegne in carriages. At the foot of Les-Beaux-Monts we saw a thin white or grey sand with a few flint pebbles lying on the white Chalk. These sands are on the same horizon as the Thanet Sand in England. A little higher up a thick mass of plastic clay and sand was in great part concealed by vegetation, the top of the hill being occupied by other buff sands with siliceous nodules belonging to the Sables de Cuise, but here without fossils. Near Vieux-Moulin and the Vivier of Frere Robert we found the same plastic clay, but this containing Ostrea bellovacensis (Elage sparnacieni, and near the station Vieux-Moulin there may be seen on the top of the argillaceous and lignitic beds a formation consisting of black pebbles. These black pebbles make a very important and extended layer covering South England (Oldhaven Beds), north France, and a part of Belgium. A long study of these pebble-beds has been made in England by Mr. Whitaker, and I have done the same in France. In adopting the name of Saoies de Sinceny, many years ago, I placed this formation at the top of the Lignites of Soissonnais, but since new observations made in the north of France by M. Leriche I incline now to put it at the bottom of the Sables de Cuise as the outcome of a marine invasion transgressing over various precedent stages. The most interesting point is near the Etangs of 51. Pierre, on a road leading to the little village of Cuise. The following section can be visited very easily, and the sandpit full of shells is at some hundred yards within the wood: SECTION TAKEN IN THE ROAD ASCENDING TO CUISE LAMOTHE (OISE). Metres. ( R ough limestone, yellowish, mostly broken. }' Glauconitic limestone (Calcaire grosster m/i,-ieur). LOWER i Sandy limestone, yellow and green. with numerous CALCAIRE Nummulites Ia?Vlgatus. about 6 GROSSIER'l Calcareous glauconitic sand with numerous grains of hyaline quartz and black pebbles of flint, broken shells, teeth of squales. Plastic glauconiferous clay (level of water), Argile de St Gobain, Paniselien of Belgium. ⢠⢠⢠r Glauconiferous grey sand with many Nummulites planulatus and Turritelia Solanderi . ⢠. ⢠Same sand, obliquely stratified, Alveolma. ⢠⢠SABLES DE Grey sand, without any fossil . . . ⢠⢠CUISE. 1Grey and green. sand, full of fossils, Cyrena Graoesi, Ostrea, I otamides ⢠. ⢠⢠. ⢠⢠Greensand with some sandstones. ⢠⢠⢠⢠Argillaceous sand, glauconitic ⢠⢠⢠⢠â¢
  • EXCURSION TO PARIS. The state of preservation of the fossils is excellent. About 300 distinct species have been recorded j a large part are fluvio- marine, e.g., c..vrena, Me/anopsis, Potamides, Neritina; others, purely marine, are for the most part the same as those of the London Clay. On gaining Pierrefond for luncheon, we made some short observations. The top of all the hills is occupied by the lower part of the Calcaire grassier, and the limestone and sand with Nummulites lavigatus assumes a great importance. Some other beds are full of Ditrupa, and of little Echinoderms, as Lenita lJatellaris, Seute/laria rotunda, Seutellina nummularia. The environs of Pierrefond show very important examples of dolomitisation of the Calcaire grower. We have proved this alteration to be much posterior to its formation, and extended to many other rocks, as the chalk, the sandy limestones of the Sables moyens, etc., but the process of transformation remains obscure. The glauconiferous hard limestone is changed into a thin, soft, yellow sand, without fossils, and showing under the microscope little rhombohedral crystals of double carbonate of calcium and magnesium. We had only time in the afternoon to pay a visit to the Castle of Pierrefond. It is in a very fine situation. It was a very old and large castle, re-built by the architect Violet Leduc by order of the Empress Eugenie exactly as it was during the Middle Ages. REFERENCES. 1863. HEBERT.-Bu!!. Soc. Geot., vol, xx, p. 605. 1872. ----.-Bull. Soc. Geo!., vol. xxix, p 446. 1873. ----.-Bu!l. Soc. Geol., voL xxix, p. 583. 1880. G. DOLLFUS.-" Essai sur Ie determination de I'age du soulevement du Pays de Bray." B. S Geol, vol. ix, p. II2. 18go. ------." Recherches sur les Ondulations des Couches Tertiaires, dans Ie Bassin de Paris." Bul!. Service Carte Geol., No. 14. 1900. -----. "Relations entre la Structure Geologique du Bassin de Paris et son Hydrographie." Annals ae Geographie, vol. ix, p. 50. Igoo. -----. "Structure du Bassin de Paris." Assoc. Franc. Avanc de Science, Paris, p. 546. Igoo. '--. "Derniers Mouvements du sol dans Ie Bassin de Paris et de la Seine." Compte Rendu Congres Geol., International, Paris, rcco. Ig03. ------. "Nouvelle Carte Geologique du Bassin de Paris au Millionieme.' Bull. Soc. Geot. vol. iii, p. 7. Much useful information can be found in the Bulletin des Sermces de la Carte Geologique de France from 1894 to 1908, and geological maps at the scale ..-obn.
  • CLASSIFICATION G~N~RALE DES COUCHES DU BASSIN DE PARIS. PERIODE QUATERNAIRE (Pleistocene). Bas niveaux.-Litnons et graviers du fond de la vallee de la Seine, faune Iroide, Elephas primigtnius, instruments de silex melanges, varies. Noyens n,vtaux.-Limons a briques, sables varies, faune temperee, Elephas antiquus, Hippopotame, instruments chelleens, Hauts niveaux.-Limons et cailloux culmiuants, faune chaude, Elphas trogofltMri cf, E. mlridiOflalis. ENGLISH EQUIVALENTS. QUATERNARY. Lower gravels and sands with Elephas iJrimigenius, Cercus tarandus, Various imple- ments. Northern fauna. Middle gravels and loam, with Eleplzas antiquus, Hypopotamus major, Rhinoceros Merck;;, Corbreulajluminalis, Belgrandia marginata, Warm climate; palreolithic implements. Upper gravels and glacial drift in the north. Cromer beds (in part}, Elephas meridionalis, Rude implements of the higher plateaus of Kent. PERIODE TERTIAIRE. MIOCENE MOYEN-Etage Burdigaliefl. Sables granitiques de Lozere (Sables de la Sologue et Sables de I'Orleanais avec Melanoides, Escheri et .Dinatherium). MIOCENE INFERIEUR-Etage Aquitanim. \ 2. Calcaire de Pithiviers (calcaire de Beauce superieur) avec Helix luc ) bardtnsis, H. Noudi, Limnea pach;vgaster et Anchitherium. { I. Argile du Gatinais aHeli» Aureliantnsis. OLIGOCENE SUPERIEUR-Etage Stampun. 6. Caleaire d'Etampes (calcairede Beauce inferieur) a Limnea Brongniarti, Helix Ramondi, Potamides Lamarcki et Anthracot1lerium. 5. Sables d'Ormoy a Cardit« Bazini (Fontainebleau superieur). 4. Sables et gres de Vauroux, Poudingues de Saclas, Calcaire de Darvault, 3. Sables de Morigny et Ieur aPectunculus obovatus,et Cytherea incrassata, Clrithium trochlear«, 2. Molasse d'Etrechy a Natica crassatina et Cerithium plica/14m. I. Matnes de Lonjumcan a Ostrla longirostris et Ostrea cyathula. TERTIARY. MIDDLE MIOCENE. Wanting. LOWER MIOCENE. Wanting. UPPER OLIGOCENr;;. 2-6. Upper part wanting. 1. Hamstead Series, upper marine beds, Sandy clay, with Corbula sub pisum, Volu/a Rathieri, Ostrea cyathula. OLIGOCENE INF:ERIEUR-Etage Sannoisien, 8~ Calcaire et MllUli&-e de. Brie a Nysti4 JJJ., Chasti Ii, cal. de Chateau Landon aLsmnea .Durandi. 7. Argile verte de la Brie avee rognons verdatres, 7-8. Harnstead Series. Lower Beds. LOWER OLIGOCENE. ~ 3. Variegated clays with Nystia o« Chasl,lt; Unio, seeds.2. White rnlnd with C.rithium inornatum, C. Sedgwzeki, C. plicatum.I. Black band, with Vioipara, Nematura vupa. 6. Argile marneuse, stratifies, de Romainvil1e avec Psammo;ia plana, C)1"Ina ionvexa, Cerithium plicatum. 5. Marne blanche de Pantin a Limnea strigosa, Planorbis planulatus, Nelanops.u, Xyphodon. 4. Marne bleue d'Argenteuil a vegetaux et Plagiolophus minor (Paleo- therium), 3. (1.) Haute masse de gypse saccharoide de Montmartre, Sannois, &c., a Paleotheri". magnum; calcaire de Champigny. 2. Marne a Silex Menilite. I. (II.) Seconde masse de gypse stratifie a lits crista llises. 5-6. Bembridge Series. 1-4. Osborne Series. j3' Marls of Bembridge and Wbi~.tliff, Cyrena sonistriata, Cen/hium plzeatUl1i.)Melanopsis fusiformis,2. Oyster beds, Ostrea uectensis, Cytherea sncrassata. J. Limestone of Sconce Point, Glandina costellata, Amphidromus ellipticus, Helix ~ globosa, H. d' Urbani and Paleotherium, Anoplotherium, etc. f 3· Whitish and coloured marls withPlattorbiseuomphalus, P.planulatus,Melania excaoata,2. Grey and Ferrugineous beds with Vivipara, Nelanopsis carinatus, Chara,1r. Concretionary limestone with Planorbis planula/us, Limnea strigosa, Red and green clay with Plagiolophus minor. { 6' 5· ·4, 3· { 2. I. EOCENE SUPERIEUR-Etage MarineS/en. Marries gypseuses jaunes a Turritella incerta et Lucina inornata, (Ill.) Troisieme masse de Gypse. Marnes jaunes aPholadomya Ledensis, (IV.) Quatri~memasse de Gypse. Cakair4 1a.l:Ui1!:~ da. ~msy-Ie.see a .I.ymne IolJ{fi.l&ata. Sables de Marines, Crenes, Le Rueil a Coroula pisum. Caleaire de St. Ouen aLimnea longiscata et Limnea pseudopyramidalis. Sables et gres de Mortefontaine a Aviculafragzlis. 4-6. Headon Series. Long Mead End Sands. 1'3. Barton Series. UPPER EOCENE. { 8. Blue and Yellow clay and marls, Limnea, Planorbis, Vivipara, Upper Beds Potamomya, 7. Limestone carbonaceous or sandy: Planoroiseuomphalus, Limnea, { 6. Blue clay and sands, Cerithium concauum, C. pseudocinctum, ()ren:z obouata, Middle Beds 5· Variegated Clay (Venus bed), Cytherea incrassata, Natica depressa (Brockenhurst fauna). 4. Sands and clay (NwitiRIZ bed), NerJtina concava, Cyrena deperdita. C,r#h,um vlntr,eosum. 3. Cream coloured limestone with Limnea longiscata, Lower Beds J 2. Green clays, Cyrena pu!chra bed, numerous Potamomya.1I. Sandy clays, Cyrena cycladiftrmis beds with Cerithium duplex. {4-6. Headen Hill Sands. Yellow and pure white sands, few fossils. J :J. Sandy fossiliferous clay, Tlfnoeilum sopiff4m, Vol.da IIttmerosa, Pyrula next/is, Chama squamosa. 12. Blue and grey clay, very fossiliferous.I. Green and sandy clay with Nummulites OrOign)'i,Typhis pungens, Voluta luctatri», EOCENE SUPERIEUR-Etage Auoersun, ~ J6. Calcaire de Ducy a Limnea aremdaria.I 5. Sables d'Ezanville a Potamides scalaroides, 1 \4· Sables et gres de Beauchamp a Cerithium tuberculosum. ~ 3. Sables et gres d'Ermenonville aPortunus Hericarti. , 2. Sables et gn!s caleariferes du Guespel a .Dentalium grande. I. Sables et gres d'Auvers-sur-Oise aNummulites variolarilH. 5-6. Laminated clay, sand, and lignite of Ashey, flint pebble bed. { 4' Blue and greenish clay with Nummulites oarioiarius, Turritella sulcifera, Cassidaria 1-4· Upper Brackle- nodosa. sham Beds 3. Light coloured sand with Tellrna donacialis. (Upper 2. Dark sandy clay fun of Corbula p,sum, N. vanolanus. Bagshot). r. Sandy clay and pebbles with Sanguinolaria hollowaysz. MIDDLE EOCENE. 8-13. Break in the succession. { 4' Greensand with Nummulites lcevigatus var. 1-7· Lower Ilrackle- 3. Light and dark coloured foesiliflJrous! greensand, Voluta spinosa, Turritella sham Beds terlbellata. (Lower 2. Caleareous beds (Selsey beds), Turritella imbricataria, Cardzla planzcosta. Bagshot). I. Sandy clay with black rounded flint pebbles, Nummulites lcevigatus. Sandy c1a.y, Ostrea bellovacensis, Cerithium funatum, .lfelanatria inquznata Reading beds, plastic clay, with pebbles, bones, and plants; Alum Bay strata in the Hampshire basin. flints Canterbury beds, line or calcareous sandstone, Cerbula reguloiensrs, Nalita depressa. Rochester beds, bluish grey and sandy marls, Cytherea orbicularzs, Cardium semigranulosum. Brown and green clay and sand, Pholadomya Koninckei, Cyprina ,110rrisr. Basement bed with greenish pebbles of flint. Bognor beds in the Hampshire basin. { 4' 3· 2. I. LOWER EOCENE. ·3. Various sand and laminated clay with plants. Pipe clay of Alum Bay. { 2. London clay proper with septaria and pyrites. Nautilus and many fossils. I. Basement bed of the London Clay and Oldhaven beds, black rounded Cyrena cordata. 1-4. London Clay. 1-3. Thanet Sands. 1-3. Woolwich Beds. 3. Sables de Chalons sur Vesles, Chenay, Rilly, aPectunculus terebratularis· 2. Sables de Bracheux a Cyprina scutellarra. l. Tufeau de la Fere a Pholadomya Koninc!.,i. EOCENE MOYEN-Etage Lutlcim. f 13· Marnes blanches de Nanterre a Lophiodon. 12. Cal caire caillasse a (ardium oblzquum et Cerithium B lainvillei. II. Caleaire tabulaire a SphtPnia rostrata. 10. Caleaire dur a Potamides lapidum et P. ,,'is/atum. 19. Caleaire a Milioles superieur a Cerith. dEnticulalum, Nahea parisiensrs,Lucrna saxarum. Calcaire de Provins a Planorbis pseudo-ammonius.8. Marne verte, argile grise (Bane vert) a Potamides. { 7. Calcaire a Milioles lines (Bane royal) a vegetaux, Cardium aviculan, Lucina ioncentrica. 6 Caleaire de Parnes a Orbitolites complanata. 5. Caleaire de Grignon a Turritella imbrica/aria. 4. Caleaire grossier a Cerithium (Campa"ile) giganteum. { 3. Caleaire glauconieux a Ditrupa, Cardium porulosum. 2. Caleaire sableux, verdatre, de Chaumont aCardr/a planicosta, polypiers, echinides. I. Sables gla uconiferes et caleaires a Nummulites lcevigatus. EOCENE INFERIEUR-Etage Cuisien. 4. Sables argileux de Laoll, Belleu, Craonne (Paniselien). 3. Sables de Cuise·Pierrefond a Nummulitesplanulatus, Tzerritella Solanderi. 2. Sable d'Ai2y-Jouy a Ostrea rarilame!la. I. Sable graveleux galets noirs de Sinceny, Pourcy a Faunus Dujrlsnn: EOCENE INFERIEUR-Etage Sparnacien. 3. Marnes et argiles de Vaubuin a Ostrea Btllovacensis. 2. Argiles ligniteuses d'Epernay, Rilly 11 CerJthium funatum. Argile plastique de Vaugirard. I. Sables et conglomerat de Cernay-Meudon a Coryphodon. Sables granitiques du Breuillet, Pondingue de Nemours. EOCENE INFERIEUR-Etage Tlzanecien. 4. Caleaire de Rilly-la-Montagne a Physa gigantea. PALEOCENE-Etage Montien. Caleaire pisolitique de Meudon, Beynes, &c. PALEOCENE. Wanting. PERIODE SECO:-\DAIRE. TERRAIN CRETACb-Etage Sinomtn. Craie blanche de Meudon aBelemnitilia mUC1'onata et Magas pumilus. Upper Chalk. CRETACEOUS SERIES. White chalk with flints, Belemnitella mucronata. G. DOLLFUS, November, 1908. To face PtN:1 ~I.