and include five of the species, while the remaining sixth comprises about half the species and belongs to various groups. Of the Coleoptera, fully one-half the species and about seven-tenths of the specimens belong to the Curculionidae; the others mostly to the Staphylinide and Carabidae. These two suborders, flies and beetles, comprise the bulk of the determinable objects-nearly sixsevenths of the specimens and more than five-eighths of the species. The Hymenoptera consist of a small ant, a Pteromalus-like insect, and one rather obscure form. The Hemiptera are represented by an insect resembling Issus and another apparently belonging to the Tingida. In the Orthoptera there are only legs of a Locustarian about as large as our common Phylloptera and a cricket, perhaps of the genus Nemobius. Two Phryganeids are represented by wings, one of them doubtfully located in this family. Of the gally worm and spiders little can be said.

The interest in these objects is greatly increased when they are compared with the others brought from the same region. In the first place, the shales from "Chagrin valley" and "Fossil Cañon," are dark gray in tint, while those containing the insects now under discussion are of a reddish clay-color; the former are much more closely grained and of a firmer texture, resembling lithographic stone, and the objects are consequently better preserved – indeed on some slabs the hairs along the edge of a wing in a Thrips may be counted.

--

Again, the fauna of the several localities differ. We have already remarked in a previous paper that this is the case with the specimens from Chagrin Valley and Fossil Cañon, although the stones themselves are similar in character. Mycetophilide and other Diptera are found in both places, "but in Fossil Cañon, the variety and abundance are proportionately greater; the ants, the moths, the Thrips and nearly all the smaller Coleoptera are restricted to Fossil Cañon, while the larvæ come from Chagrin Valley." The same is true of Mr. Richardson's specimens; not a single species can be definitely referred to any of those found by Prof. Denton, and the assemblage of species is different: thus, a single fragment of an elytron is the only Curculionid in the Chagrin Valley shales, and probably it is generically distinct from all those mentioned above. The type of fly spoken of as so abundant in the shales collected by Mr. Richardson is represented in the previous collection only by a single specimen from Fossil Cañon,

probably belonging to a different genus. The two forms mentioned under the name of Issus, one from Richardson's shales and the other from Chagrin Valley, are not congeneric; and the same is probably true of the ants from these shales and from Fossil Cañon. It is in the Mycetophilide and Tipulido, however, that we find the closest resemblance between the different collections; in the comparative abundance and variety of these insects, the shales worked by Mr. Richardson may best be compared to those of Fossil Cañon, but in the former the specimens are too poorly preserved to make a close identification very satisfactory; the genus Dicranomyia is apparently found in all three localities. Compar ing the assemblages of species, we find that Diptera and Coleoptera are the prevailing forms in each, but that within these groups the types differ in a remarkable manner, according to their several localities; the Orthoptera and Neuroptera, the spiders and Myriapoda of the later discovered beds are wholly wanting in the earlier; the Lepidoptera and Physopoda are found only in Fossil Cañon, and no trace of ants appears in Chagrin Valley, though occurring in the other two places and also in the locality examined by Dr. Hayden.

*

These results should not surprise us, since in the two rich quarries of Eningen, Baden, one of which is only a mile distant from, and about one hundred and fifty feet above the other, the insects are found to be specifically distinct throughout. Probably some of these conclusions will be modified by a more searching study of the remains under examination; unquestionably they will be altered by further researches in the field; and certainly these tertiary beds of the Rocky Mountains appear exceedingly rich in insect remains, and are worth careful exploration; that they extend over several successive geological stages seems probable from the great diversity of character in these fragmentary collections, and also from Prof. Denton's statement that the shales in which they occur have a thickness of a thousand feet.

* All the insects as a rule are rather small in size.

THE GEOLOGICAL AGE OF THE COAL OF WYOMING.

BY EDWARD D. COPE, A.M.

In his Geological Survey of Wyoming, Professor F. V. Hayden thus describes the great coal area of Wyoming. "About two miles west of Rawling's, springs begin to appear again, and at Separation Platanus Haydenii, Cornus acuminata and other undetermined species of plants occur. This point forms the eastern rim of a basin which extends about one hundred and ten miles to the westward. A new group comes in which I have named the Washakie group, from the fact that near this station are beds of calcareous sandstone and limestone, composed of an aggregate of fresh water shells. As they are mostly casts it is difficult to identify the species, but Mr. Meek has named the most abundant kind, Unio Vasakei. Soon after leaving Bitter Creek, coal strata of Eocene age rise to the surface from beneath the surface of the Miocene beds of the Washakie group, with a reversed dip. Here we find numerous beds of coal, and in the rocks above and below the coal, are great numbers of impressions of leaves, and in the clay, oyster shells of several species. At Black Buttes Station eight hundred and fifty miles west of Omaha, we find Sabal Campbellii, Rhamnus elegans, etc. At Point of Rocks farther west, Platnus Haydenii, Cornus acuminata, etc., occur. At Hallville the black slaty clays forming the roof of one of the most valuable of the coal beds of this region, are crowded with bivalve shells, two species of which Mr. Meek has named Cyrena fracta and C'. crassatelliformis, regarding them as Tertiary. They are undoubtedly brackish water forms, and show a sort of middle position, that is middle or upper Eocene. That there is a connection between all the coal beds of the west I am prepared to believe, yet until much clearer light is thrown upon their origin than any we have yet secured, I shall regard them as belonging to any transition series or beds of passage between the true Cretaceous and the Tertiary. It will be seen at once that one of the most important problems in the geology of the West awaits solution, in detecting without a doubt the

*Read at the Dubuque Meeting of the American Association for the Advancement of Science. Aug., 1872.

age of the coal series of the west, and the exact line of demarcation between the Cretaceous and Tertiary periods." (Report 1870 pp. 164-5.) Thus Prof. Hayden left the subject at that time.

In passing over the region from Ft. Bridger to Black Buttes during the present season, I traversed successively the strata of the Bridger and Green River epochs. Near Rock Spring Station the coal group makes its appearance, rising from beneath the Green River strata, as it appeared to me without instrumental aid with some degree of uncomformability. This forms the western border of an upthrust of rocks of which Dr. Hayden has treated in the above extract. At Rock Spring eleven coal beds have been struck in shafting, of which the upper and thickest is ten feet in depth. The rocks are buff sandstone nearly worn, alternating with gray sandstones and shales. They descend again near Point of Rocks and remain nearly level at Black Buttes. At Hallville I obtained isolated scales of numerous species of fishes. At Black Buttes I learned that Mr. F. B. Meek had visited the neighborhood, and had discovered the bones of some large animal. I went to the spot and found fragments of large bones lying in a bed of fossil leaves. On excavating, other bones were obtained including sixteen vertebræ, the sacrum, both ilia and other pelvic bones, with ribs and bones of the limbs. The position of the bones was in a bed of gray sandstone, above one coal bed and below two. They were covered with the leaves which had evidently falien upon them, and filled the intervals between them, and occupied the angles between the processes, the neural canal, etc., just as they had been pressed in when soft. The skeleton had fallen on the shore, for the leaf bed passed gradually into a shell bed, which included mostly thin bivalved species.

The pelvic and sacral bones, in fact every part of the skeleton proved the reptile to have been a Dinosaurian. The entire dorsal vertebra was twenty-eight inches in height and the ilium between three and four feet in length; both extremities are straight, the one massive, the other dilated and thin, with a superior process. It resembles that of Cetiosaurus more than any other but presents well defined differences. It is named Agathaumas sylvestris.

This discovery places this group without doubt within the limits of the Cretaceous period, and to that age we must now refer the great coal area of Wyoming. It is surrounded to the west and

south and perhaps to the north by Eocene Tertiary beds, and the appearance of the country indicates that a smaller lapse of time has separated the periods of their deposit than is usual. Nevertheless no traces of Cretaceous types of vertebrates have yet been found in any of these Tertiaries.

EFFECTS OF EXTRAORDINARY SEASONS ON THE DISTRIBUTION OF ANIMALS AND PLANTS.

BY PROF. N. S. SHALER.

WHATEVER throws any light upon the nature of the means whereby the changes in the character and distribution of organic forms have been effected, has for the student of geology the keenest interest. I therefore venture to call attention to the peculiar effects of the last year upon the forests and probably upon some of the animals of New England. The year preceding the winter of 1871-2 was one of the dryest on record in this region; the rainfall was not only much less than usual, but came in such a fashion as to leave the ground very dry when winter came. The snowfall during the winter was slight and did not lie well upon the ground, melting and drifting in such fashion as to leave a large part of the surface quite unprotected. In this state the long continued and steady cold froze the earth to a great depth, and at some points the frozen ground was found as far as five feet from the surface. Over the whole of New England it was doubtless deep enough to involve the whole of the roots of the vegetation of our forests. It is doubtful whether it was the intensity of the cold alone which produced the effects which have been observed all about us, but more likely that it was in large part due to the deficiency of sap in the plants, in connection with the low temperature; as the frost left the roots, they remained for some time in contact with relatively dry earth, thus causing a shock too great for their vitality to withstand. I do not see clearly just how the cold and drought coöperated in bringing about this destruction, though I have no doubt they worked together.

The tree which suffered most is the arbor-vitæ (Thuja occidentalis) for more than half of these are dead and a large part of those