implements was supposed, but not ascertained. Its interest and connection with human migrations were mentioned; also the supposition of Pomel, that the submergence of the West India Islands took place since the post pliocene period.

PROF. O. C. MARSH described a "remarkable locality of Vertebrate remains in the tertiary of Nebraska." The locality described was the Antelope Station on the Pacific Railroad in South-western Nebraska. While engaged in sinking a well at that place in June, 1868, a layer of bones was found by the workmen at a depth of sixty-eight feet below the surface, which were at first pronounced to be human, but, during a trip to the Rocky Mountains, Prof. Marsh examined the locality and the bones, and found that the latter were the remains of tertiary animals, some of which were of great interest. The well was subsequently sunk about ten feet deeper. An examination proved that among them there were four kinds of fossil horses, one of which he described in November last as Equus parvulus. Although it was a full-grown animal it was not more than two and one-half feet high. It was by far the smallest horse ever discovered. Of the other kind of fossil horses one was of the Hipparion type, or the three-toed horse. Including the above the number of species of fossil horses discovered in this country was seventeen, although the horse was supposed to be a native only of the old world, and was first introduced here by the Spaniards. Of the other remains there were two carnivorous animals, one about the size of a lynx and the other considerably larger than a lion-twice as large as any extinct carnivora yet discovered in this country. Among the ruminants found in this locality was one with a double metatarsal bone, a peculiar type, only seen in the living musk deer and in the extinct anaplotherium. There were also the remains of an animal like the hog, a large rhinoceros, and two kinds of turtles. These, together, forming fifteen species of animals, and representing eleven genera, were all found in a space ten feet in diameter and six or eight feet in depth. It is supposed that the locality was once the shores of a great lake, and that the animals were mired when they went down to the water to drink.

Prof. W. P. BLAKE read a paper "On the Plasticity of Pebbles and Rocks." He presented some fresh evidence from a conglomerate in Arizona Territory. This conglomerate consisted of a paste of micaceous schist, filled with pebbles of varying size, and elongated and compressed similar to those of the Newport conglomerate. They presented even more conclusive evidence of having been drawn out, and compressed by tension and enormous pressure, than even the Newport pebbles. Eminent geologists had alleged that deep seated rocks often became plastic and that those not much exposed to air were softer than those on the surface. Prof. Blake then adduced arguments and facts tending to substantiate this theory. The distortion of hard rocks was found on a large scale in the flanks of the Sierra Nevada of California. Prof. Blake said that the consideration of the phenomena led him to conclude that enormous and long

continued pressure and tension probably at a moderate elevation of temperature (but not necessarily so) had been sufficient to produce the molecular movement of these hard and apparently unyielding materials. Mechanical force alone appeared to have been the agent, and M. Tresca had shown that under enormous pressure solids could be made to flow in the same manner as liquids, or that in their movements they followed the same law. By the careful study of these phenomena of plasticity new views were opened of the structure of great rock masses; of the phenomena of plication, lamination; ^and of the origin of some structural peculiarities of mineral veins and their enclosing walls. In view of all the facts, Prof. Blake thought that geologists should admit that very great changes had been produced in the structure of rock masses by simple mechanical pressure, unaided by any great elevation of temperature or by extraordinary chemical agencies.

PROF. O. C. MARSH read a paper "on some new Mosasauroid Reptiles from the Greensand of New Jersey." The striking difference between the reptilian fauna of the Cretaceous period of Europe and the same period in America was that in the former there were great numbers of remains of ichthyosauri and plesiosauri, while hardly a tooth or vertebra of the mosasauroids was to be found. In America the two former kinds of reptiles appeared to be almost entirely wanting. One or two specimens found here had been alleged to be ichthyosauri or plesiosauri, but farther examination threw strong doubts on the matter. To replace these forms, however, the mosasauroids were found in abundance. The affinities of the mosasauroids were chiefly with the serpents rather than with other reptiles, although they had certain other affinities with swimming reptiles. Prof. Marsh produced some fossil remains of different specimens of mosasauroids, showing the peculiar formation of the skull. These reptiles appeared to have no hind limbs, although Cuvier thought he had detected them. The specimens found in this country, however, afforded no evidence of this. He called attention to two new forms of the family- the Macrosaurus platyspondylus and the Mosasaurus Copeanus-in which the articulation of the lower jaw was one of the most interesting features. The larger specimens of these animals showed that they must have been the monarchs of the seas of those periods, and in appearance and size not unlike the popular notion of the sea serpent, being sometimes seventyfive feet long.

"On the Flora and Fauna of the Miocene Tertiary Beds of Oregon and Idaho." Prof. Newberry exhibited a beautiful series of fossil plants collected by Rev. Mr. Condon of Dallas City, Oregon. These plants were from the fresh-water deposits which cover so large a surface of the Great Basin in Nevada, Idaho and Oregon, and were of special interest both from their geological position and botanical character. They were contained in the sediments deposited by a series of great fresh-water lakes, which once existed in the area lying between the Rocky Mountains and Sierra Nevada.

In the report of his explorations in California and Oregon, Prof. Newberry had described these lacustrine deposits and had shown how the lakes at the bottom of which they accumulated had disappeared by the cutting down of their outlets, the gorges through which the Columbia, Klamath and Pitt Rivers now flow.

The Klamath lakes, etc., were miniature representatives of these ancient lakes which were apparently quite as extensive as our present great lakes. The fossil plants contained in the collection made by Rev. Mr. Condon were most beautifully preserved, and consisted of a great number of species, most of which were new; but a number were identical with species found in the Miocene Tertiary of the Upper Missouri. There are also some species which had been found in the Miocene beds of Frazer's River and Greenland. The present collection will add much to our knowledge of the Flora of the Miocene period on this continent. The animal remains found in the same series of Tertiaries with the plants, consist of fresh-water shells and fishes, with a few mammalian bones. The shells are numerous species of Melania, Planorbis, Corbicula and Unio — all, so far as known, new to science. The fishes were Cyprinoids allied to Mylopharodon, etc., the fishes now inhabiting the Western rivers. Among the mammalian bones contained in this collection were some that plainly belonged to the horse. The beds containing the animal remains were perhaps more recent than the plant beds, but still Tertiary.

Mr. W. H. DALL read a paper "On the Trend of the Rocky Mountain Range, north latitude 60°, and its influence on Faunal Distribution." The paper stated that the Rocky Mountain Range, between latitudes 60° and 64°, bends trending with the Eastern coast, so that instead of there being, as represented on the old maps, a straight line of mountains up to the Arctic Sea, there is an elevated plateau, only broken occasionally by a few ranges of hills. This bend of the mountains prevented the characteristic birds of the west coast from coming north, while a few species of Eastern birds came clear to Behring's Sea, north of it, over the plateau. He also stated that the elevation of the bottom of Behring's Straits one hundred and eighty feet would make dry land between Asia and America, but that a deep ocean valley extended south-west from Plover Bay, just west of the Straits, along the Kamtchatka Coast.

DEDICATION OF THE MUSEUM OF THE PEABODY ACADEMY.-On the eighteenth of August, being the first day of the session of the American Association, the Museum of the Peabody Academy was formally dedicated, and it seemed peculiarly fitting that the exercises should take place in connection with the meeting of the American Association, which adjourned over in order that the members should participate in the proceedings.

At 2 P.M. a number of friends of Science met at the Museum, when a formal transfer of the building was made by the Committee of the Trustees of the original fund, to the Trustees of the Academy, and the charge of the Museum committed to the Director, Mr. F. W. Putnam. The audience then repaired to the Tabernacle Church to listen to the Dedicatory

Address by the President, W. C. Endicott, Esq. Hon. J. H. Clifford replied on the part of Mr. Peabody, the founder of the Academy, who was unfortunately absent from the ceremonies owing to his continued ill health. Remarks were made by Mayor Cogswell; B. II. Silsbee, the President of the East India Marine Society; Henry Wheatland, President of the Institute, and by J. W. Foster, President of the American Association for the Advancement of Science.

ANSWERS TO CORRESPONDENTS.

W. W. B., Indianapolis, Ind. Your specimens are as follows: 2, Onoclea sensibilis ; barren frond, common at the north and south. 3. Pteris aquitina; widely distributed. 4, Asplenium thelypteroides; found north and south. 5, a species of Galium. 6, Eleocharis olivacea Torrey. 7, no fruit, and not easily determined. If you mean by the "Snow-plant" Sarcodes sanguinea, you will not be able to cultivate it, as it is parasitical in its habits and proves very dificult to rear. Herbariums are not usually pub lished unless of rare and costly character, such as of newly discovered species like Fendler's of Venezuela, Wright's of Cuba, etc.-J. L. R.

H., Danversport, Mass.-The worm declared by your patient to have been found in the wound is a worm allied to the common earthworm, and probably lived in the muddy bottom of a well, spring, or brook, and may possibly have occurred in the water used in dressings. We have kept it alive in the bottle in which you brought it, for four or five days.

W. W. B., Indianapolis.- No. 8 is Botrychium lunaroides var. obliquum; barren frond. Hooker's Synopsis Filicum, and PresP's Pteridigraphia, are essential in study. ing the ferns extensively.-J. L. R.

W. C. F., Eastham, Mass.-The frog is Rana sylvatica.

EXPLANATION OF PLATE 7.

RADIOLARIA.-Fig. 1. Tetrapyle octacantha. Fig. 2. Haliomma amphidiscus. 3. Haliomma longispinum. 4. Haliomma hexacanthum. 5. Haliomma Humboldtii.

BOOKS RECEIVED.

Scientific Opinion. June, July, Aug., Sept. London.

Journal of Travel and Natural History. Vol. 1, No. 6. 1869. London. Two shillings. Proceedings and Transactions of the Nova Scotian Institute of Natural Science at Halifar, N. S. Vol. ii, Part 2. 1857-8. 8vo. Halifax, 1859.

Second Annual Report of the Trustees of the Peabody Museum of American Archæology and Ethnology. Boston, 1839. 8vo., pp. 23.

Pathogenesis of Ptelea trifoliata; a Report to the American Institute of Homœopathy. By E. M. Hale, M. D. Boston, 1839. 8vo, pp. 85.

American Journal of Numismatics. July. New York.

Library of Education, selected from the best writers of all countries. Scottish University Addresses. By J. S. Mill. Jas. Froude, and T. Carlyle. New York: J. W. Schermerhorn & Co. July, 1839. 32mo, pp. 192. 20 cents.

CORRECTIONS.

In our September number, in the "Chapter on Mites," we suggested that Plate 6, fig. 1, represented the larva of Dermaleichus, and that fig. 3 represented the male. We were led to this opinion by the resemblance of fig. 1 to fig. 4, the larva of another genus of mites. After the article went to press we obtamed the elaborate memoir of Claparede, entitled "Studien an Acariden" published in a recent number of Siebold and Köllikers "Zeitschrift" where he has given a minute account of a neighboring geaus, Myocoptes musculinus (Koch) found parasitic on mice. After studying Clapa rede's work we judge that our figure 1 must be a female Dermaleichus, and that fig. 3 represents the male, and fig. 2 the young male.-A. S. P.

On page 368, line 2 from bottom, and on page 373 line 10 from top, for Chelytus read Cheyletus. Page 316 line 20 from top, for Euglenia read Euglena.

On page 331, line 6 from bottom, for Orange, N. J. read Orange, N. Y.

On page 326, line 1 from the bottom, for "Mission County," read Mifflin County, Pa. The author of the article on "Table-mountain Pine" (J. T. Rothrock) also states that Mr. Meehan has since found the same pine on the hills near Harrisburg, Pa., and concludes it is native to the whole interior of the State of Pennsylvania. (See Gardener's Monthly, June, 1857, p. 173.)