of a diatom earth, and Mr. Hanks sent some lichens containing diatoms from a parapet of the Palace at Versailles.

After examining the beautiful slides of foraminifera, mounted by Mr. Merriam and exhibited by President Hyde, the members. began their contributions to the topic of the evening, "The microscopical examination of sea water, with reference to its animal and vegetable forms." Dr. Whitney spoke at some length of his physical and chemical investigations upon Pacific ocean water, taken at insetting tide just within the Golden Gate. He spoke of the lime and silica in solution in sea water, and beside attributing to these the origin of the foraminifera shells and diatom frustules, a well-known fact, spoke of the silica in solution as a probable source of sand, since he considered the fine deposit that gradually fell in his jars of sea water as coming from solution, and not as a long suspended silt, the view generally held.

After selecting for the next topic "The Lower Forms of Marine Life," the society listened to a translation, by Secretary Clark, of a short paper on "The Alternate Generation of the Echinodermata," by Prof. Haeckel.

AMERICAN ASSOCIATION For the ADVANCEMENT OF SCIENCE.The next meeting is to be held in Saratoga on the last Wednesday of August, 1879. The officers elected for that meeting are Prof. G. F. Barker, of Philadelphia, president; Prof. S. P. Langley, of Alleghany, Pa., vice-president of section A; Major J. W. Powell, vice-president of section B; Prof. Ira Remsen, chairman of subsection of chemistry and Prof. E. W. Morley, of Hudson, Ohio, chairman of subsection of microscopy. Among the noteworthy papers in geology and biology were those by C. O. Whitman on the Embryology of Clepsine, Prof. I. E. Todd's on Richthofen's Theory of the Loess in the light of the deposits of the Missouri, A. G. Weatherby's Are the so-called Chætetes of the Cincinnati Group Bryozoans? and his remarks on the Geographical Distribution of the land and freshwater Molluscs of the United States and their local varieties. Major Powell spoke on the rainfall of the arid. region of the United States, while Prof. B. G. Wilder made a communication on a remnant of the spiracles in Amia and Lepidosteus, and S. A. Forbes read a paper on the development of Amia, Mr. C. E. Dalton made a communication on the geological history of the Colorado river and plateaus, and Mr. A. Lakes spoke of the discovery of Atlantosaurus and other Dinosaurs in the Rocky mountains of Colorado. The anthropological papers were noticed in our last number.

BOSTON SOCIETY OF NATURAL HISTORY, Oct. 2d.-Mr. W. O. Crosby read notes on the physical geography and geology of Trinidad.

APPALACHIAN MOUNTAIN CLUB, Oct. 9th.-Rev. H. G. Spaulding read a paper entitled Something about Moosilauk and the Franconia Range; Prof. J. H. Huntington gave an account of the Megalloway river and its physical and topographical features, while Mt. Ascutney, Vt., was described by Mr. Frederic Gardiner, Jr.

SCIENTIFIC SERIALS.1

PROCEEDINGS OF THE ROYAL GEOGRAPHICAL SOCIETY.-July 6, August 16, No. iv. On the Nyassa and a journey from the north end to Zanzibar (with a map), by H. B. Cotterhill. Travels in Western China and on the eastern borders of Tibet, by W. J. Gill. On the Geographical results of the Mission to Kashgar, under Sir T. Douglas Forsyth, in 1873-4, by H. Trotter. No. v contains the president's (Sir Rutherford Alcock) address. No. vi Geographical sketch of the Nile and Livingstone (Congo) basins, by H. M. Stanley. A lecture on plant-distribution as a field for geographical research, by Thistleton Dyer.

SIEBOLD AND KÖLLIKER'S ZEITSCHRIFT FÜR WISSENSCHAFTLICHE ZOOLOGIE.-September 6. Contributions to a knowledge of the Julidæ, by E. Voges. On the formation of the blastoderm and the germinal layers in insects, by N. Bobretsky. Additions to a knowledge of the genus Brisinga, by H. Ludwig. Aspidura, a genus of mesozoic Ophiuridæ, by H. Pohlig. Fifth article on the structure and development of Sponges. The metamorphosis of Sycandra raphanus, by F. E. Schulze.

THE GEOLOGICAL MAGAZINE.-August. On the form of Volcanoes, by J. Milne. On a method of estimating the extent of Geological Areas, by T. M. Hall. September.-Notes on some Arctic Silurian fossils from Beechey island and from Port Dundas, Lancaster sound, by H. Woodward. Cataclysmic theories of Geological Climate, by J. Croll. Land plants in the Irish Silurians, by G. H. Kinahan. Wayside notes in travels over Europe: the great Northern drift, by R. Damon.

THE GEOGRAPHICAL MAGAZINE.-September. The Treaty of Berlin (with a map). Richthofen on Prejevalsky's journey in Central Asia, Abyssinia. A new Survey of the Amazon. Indian irrigation, by H. P. Malet.

PSYCHE.-March and April. The Entomological writings of John L. LeConte, compiled by Samuel Henshaw, edited by George Dimmock. Oviposition in Spiders, by J. H. Emerton.

The articles enumerated under this head are usually selected.

THE

AMERICAN NATURALIST.

VOL. XII. DECEMBER, 1878. No. 12.

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THE EXCURSIONS OF THE GEOLOGICAL SOCIETY OF FRANCE FOR 1878.

THE

BY E. D. COPE.

HE Geological Society of France, though well known in the United States as a publishing body, is not so well known as a school of experts who give practical instruction in their science. In their annual excursions they offer opportunities for acquiring special knowledge in geology of peculiar value. The present season the excursions were arranged in view of the presence of numerous foreigners for a limited time in Paris, so as to exhibit the geology of the country near to, or within easy reach of the capital. There were seven in all, and each one was in charge of a competent geological instructor, while the financial department. was under direction of the indefatigable treasurer of the society, Dr. Bioche. A better opportunity of becoming acquainted with the standard of classification of the Tertiary formations which France furnishes to the world, could scarcely have been presented; while the series of beds of the Cretaceous and Upper Jurassic formations visited by the excursionists is, in many respects, very complete. The explanations on the ground furnished by the masters of the subject was all that could be desired for clearness and pains-taking. The leaders of the excursions were Messrs. Hèbert, Lapparent, Tournouer, Vèlain, etc. Among the excursionists we noticed, besides the resident members; M.M. DeWalck, Rutot and Lefevre, of Belgium; M. Stephanescu of Belgrade; M. Renevier, Lausanne; Prof. Guisgardi, Naples; Profs. Almera, Barcelona, and Eulate, Madrid; Fontannes, Lyons; Matheron and Saporta, Provence, and many others.

The first expedition was in the immediate vicinity of the northwest part of Paris, to Vanves, Meudon and Bellvue. At the first

named locality, a beautiful section of the Lower Eocene or Suessonien was examined, which displayed principally the Argile Plastique, below the thin beds of the Lignite of the Coryphodon, Gastornis and Palæonyctis. The whole was crowned by massive beds of the Calcaire Grossier of the Middle Eocene, with its numerous invertebrate fossils. I viewed these exposures with great interest, as the formations contain the remains of a fauna which I rediscovered in New Mexico in 1874. By this discovery I was able to identify the Wasatch horizon of the Rocky mountains with the Suessonien, thus establishing a basis for comparison of formations above and below it, a want not a little felt in North American palæontology. But how different the petrography of the Paris basin from that of North-western New Mexico. Here a thick bed of tenacious lead-colored clay is surmounted by a stratum of more or less impure lignite; in New Mexico heavy beds of hard sandstone alternate with still thicker red and yellow strata of arenaceous marl.

The Calcaire Grossier here yielded its numerous Echini, Cardita planicosta, Nautilus, etc. Further on, along the road towards Meudon, its softer beds formed the banks on either side. Here they were almost composed of two species of Nummulites, N. lævigata and N. lamarckii. Still beyond we visited one of the quarries whence had been obtained many huge blocks of the soft limestone from which so large a part of the city of Paris has been built, and to whose yielding qualities so much of the architectural beauty of the Capital of France is due. Here some of the desolating effects of the German siege were still to be observed. The lowest Suessonien, the Marnes Strontianiferes with their curious mixture of the marine and fresh water shells of the Calcaire Grossier and sands of Rilly, recently discovered, were passed as a white bank on the side of the public way. At Meudon the upper beds of the Cretaceous came in view. The contact of the Pisolitique (Mæstrichtien or Fox hills) with the Marnes Strontianiferes above, was noted as the point of separation between the Tertiary and Cretaceous series. The situation. is as though the Wasatch rested immediately on the Fox Hills beds, without the intervention of the great Laramie series; although the Marnes must be regarded as lower in the scale than the lowest Wasatch yet found in North America. A fine exposure of the Chalk, with its characteristic fossils, succeeds the Piso

litique downwards, and various characteristic fossils were found, including previously unsuspected species of the American genera Empo and Saurodon.

1

An agreeable feature of the occasion was a lunch offered by Prof. Chancourtois, member of the society, in his garden at Meudon, which was appreciated as such occasions generally are by hungry geologists.

The excursionists then examined the orange sands and sandstone of the Lower Miocene, at Bellevue, called the Sables de Fontainebleau, well known as the horizon of the Halitherium. From this point the quarries of the upper beds of the Lower Miocene, of the Meulières de Beauce, were visited. This formation, extensively distributed near to Paris, consists of red and yellow clay, filled with large siliceous concretions which contain the casts of great numbers of seeds of Chara and small Lymnaea. At this locality it forms the summit of a hill, from which a magnificent view of the country to the eastward is had. At its foot is the valley of the Seine, abounding in villages, villas and vineyards, and on its opposite side a range of hills bounds the horizon. The most elevated portion of the ridge bears the fort and hospital of Mount Saint Valerien.

The second excursion was to Etampes, Morigny and Jeurres, at a distance of thirty-five miles from Paris. It passed over the Miocene beds above mentioned, and visited some richly fossiliferous localities of the Sables de Fontainebleau.

The third excursion was to Maignelay, at about the same distance from Paris, where the party explored the lignites of the Suessonien, and the lowest bed of that formation, the Sables de Bracheux.

On the 9th of September the excursionists took the rail to Gournay, on the border of Normandy, from which point they passed on foot and by omnibus over a hilly and beautiful country. The region is rich and one of the most beautiful in France. The farmers have left and planted many trees, and the agriculture is of a superior character. Here under the direction of M. Lapparent, the party viewed the outcrops of the Kimmeridge, Portland, Neocomien, Greensand, Gault, and Cenomanien, and collected Trigonia, Gervillia kimmeridgensis, Hybodus, Terebratula, with numerous species of Ostræa, and Exogyra, etc. The dinner.