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eighteen misspellings out of a total number of 768 specific and subspecific names, and the generic and other names accompanying. These are of course not due to ignorance on the part of the members of this body, some of whom are distinguished for scholarship, but because of an extreme view of the law of priority.

In closing I wish to utter a plea for euphony and brevity in the construction of names. In some quarters the making of such names is an unknown art. The simple and appropriate names of Linneus and Cuvier can be still duplicated if students would look into the matter. A great number of such names can be devised by the use of significant Greek prefixes attached to substantiatives which may or may not have been often used. Personal names in Greek have much significance, and they are generally short and euphonious. The unap

propriated wealth in this direction is so great that there is really no necessity for poverty in this direction. It should be rarely necessary, for instance, to construct generic names by adding prefixes and suffixes of no meaning to a standard generic name already in use.

SOME LOCALITIES FOR LARAMIE MAMMALS AND HORNED DINOSAURS.

BY J. B. HATCHER.

It is the purpose of this paper to give brief but accurate descriptions of the localities for the most important and best preserved specimens of Laramie mammals and horned and other dinosaurs collected by the writer for the U. S. Geological Survey, and now carefully stored in the Yale Museum at New Haven; with a map of the most important locality at present known and suggestions to collectors visiting this, or other localities as to the most promising places and best methods to be employed in order to attain the greatest degree of success.

History of the Discovery of Laramie Horned Dinosaurs.

As early as 1872, Professor Cope' described under the name of Agathaumas sylvestre a portion of the skeleton of a horned dinosaur from Laramie beds near Black Butte in southwestern Wyoming. In various publications from 1874-1877 which appeared in THE AMERICAN NATURALIST, Proceedings Philadelphia Academy Sciences and Bulletins of the U. S. Geological Survey, Cope has added much to our knowledge of these strange forms, chiefly from material collected by himself and Mr. Charles H. Sternberg from the vicinity of Cow Island on the upper Missouri River in Montana.

In 1887 a new locality for horned dinosaurs was found near Denver, Colorado, by Mr. George L. Cannon. The most important specimen, consisting of a pair of horn cores, was sent to Professor Marsh for identification and description. They were not characteristic, and owing to their striking resemblance to the horns of certain fossil Bisons, they were referred by Marsh to that genus and described under the name of Bison alticornis; the beds in which they were found being referred to late Pliocene and denominated the Bison beds."

In 1888 the writer secured in the same locality in which Cope had operated in 1875 and 1876 on the upper Missouri, parts of several skulls of a horned dinosaur, some of which Marsh has described, creating for them a new genus Ceratops, and several new species. A comparison of the types of Cope's Monoclonius recurvicornis and Marsh's Ceratops montanus, both from the same locality in Montana, would doubtless establish the generic identity of the two.

Not until 1889 was a locality found where remains of these animals were sufficiently abundant and well preserved to afford material which would give us an adequate idea of their structure and habits. In the fall of 1888 the writer's attention was called to a pair of horncores belonging to Mr. C. A. Guernsey, of Douglas, Wyoming. Upon inquiry it was learned that they had been taken from a huge skull found by Mr. E. B. Wilson 1 Proc. Am. Phil. Soc., 1872, p. 482.

2 See notice of new Fossil Mammals, Am. Jour. Sci., Oct., 1887.

on Buck Creek, some of 35 miles north of Lusk, Wyoming Early in the spring of 1889 the writer proceeded to Lusk, near which place Mr. Wilson still lived, and easily succeeded in getting that most accomodating gentleman to show him the skull from which he had taken the horns. This has proved a most important locality, and material obtained from it has increased many fold our knowledge of the Laramie reptilian and mammalian faunas. In the nearly four years spent by the writer in working these beds, 31 skulls and several fairly complete skeletons of horned dinosaurs were secured, besides two quite complete skeletons of Diclonius (Claosaurus), about 5000 isolated jaws and teeth of Laramie mammals and numerous. remains of other dinosaurs, turtles, lizards, birds and fishes, as well as extensive collections of freshwater invertebrates from the same beds. In all over 300 large boxes of fossils were collected for the U. S. Geological Survey, and are now carefullystored in the Yale Museum, many of them as yet unopened.

At present remains of horned dinosaurs are known from only four widely separated localities; one of these, that of Black Butte, Wyoming, is west of the main range of the Rocky Mountains, and the other three including the Denver locality in Colorado; the Converse Co. locality in the extreme eastern portion of central Wyoming, and the Judith River or Cow Island locality in northern Montana, lie east of the main range. There are other localities known to the writer, but they are as yet of minor importance, since little collecting has been done in them and no material has been described from them. They will be referred to later.

The Ceratops Beds.

In the American Journal of Science for December, 1889, Professor Marsh applied the name Ceratops beds to certain strata in the west from which horned dinosaurs had been secured. He did not then, nor has he at any time since, designated just what he considered the geographical distribution of these beds nor their upper and lower delimitations in the geological scale. In order that the reader may not be misled in regard to Professor Marsh's position on this question I will quote him some

what fully. In speaking of the horned dinosaurs in the publication just cited he says: The geological deposits, also, in which their remains are found have been carefully explored during the past season, and the known localities of importance examined by the writer, to ascertain what other fossils occur in them, and what were the special conditions which preserved so many relics of this unique fauna.

"The geological horizon of these strange reptiles is a distinct one in the upper Cretaceous, and has now been traced nearly eight hundred miles along the eastern flank of the Rocky Mountains. It is marked almost everywhere by remains of these reptiles, and hence the strata containing them may be called the Ceratops beds. They are freshwater or brackish deposits, which form a part of the so-called Laramie, but are below the uppermost beds referred to that group. In some places, at least, they rest upon marine beds which contain invertebrate fossils characteristic of the Fox Hills deposits." Italics mine.

If we accept literally Marsh's statement that the Ceratops beds have been traced for eight hundred miles along the eastern flank of the Rocky Mountains, it will be necessary to suppose that he includes in the Ceratops beds not only the beds in Converse Co., Wyoming, but also the Bison beds (Denver beds of Cross) at Denver, and the Judith River beds on the upper Missouri. These are very widely separated localities, and no attempt has ever been made to trace the continuity of the strata from the one to the other, nor is it at all probable that such an attempt would meet with success. Professor Marsh did in the autumn of 1889 spend nearly two days in the Converse Co. locality, and again in 1891 he spent one full day in the same locality; but his time was occupied in visiting a few of the localities in which dinosaur skulls and skeletons and Laramie mammals had been found. No time was taken to determine the upper and lower limits of the beds or to trace the outcrops of the strata. After his visit in 1889 when he spent nearly two days with our party in the Converse Co. locality, he took the train for Denver, and in the company of Mr. George L. Cannon of that city, he spent one-half day examining the Bison beds (Denver beds). This constitutes Professor

Marsh's field work in the Ceratops beds. In a total of three and one-half days field work he seems to have found sufficient time to "carefully explore" the geological deposits of the Ceratops beds and to trace them for "eight hundred miles along the eastern flank of the Rocky Mountains," besides making numerous other observations of scientific interest.

Of the many interesting vertebrate fossils described by Professor Marsh from the Ceratops beds, those from the Denver locality were secured by Messrs. Cross, Eldridge and Cannon, and those from Wyoming and Montana by the writer or men in his party, with one exception only, namely, the type of Hadrosaurus breviceps, which was received at New Haven many years ago, the locality on the label accompanying it being given as Bear Paw Mountains, Montana, which is of course incorrect, it doubtless is from the vicinity of Cow Island. With this one single exception I can confidently state that all the material described by Professor Marsh as from the Laramie or Ceratops beds of Wyoming is, without exception, from Converse Co., and was found within an area not exceeding fifteen miles in width from east to west by thirty miles in length from north to south; and all the material described by him as from Montana, with the one exception mentioned, was found on the Missouri River between the mouth of Arrow Creek, just above Judith River, and the mouth of Cow Creek, some fortyfive miles below, and never back farther than ten miles from the Missouri. It will thus be seen that the actually known area of the Ceratops beds is indeed very limited, and from these areas we should exclude certainly, the Judith River or upper Missouri and very likely the Black Butte locality in southwestern Wyoming. The beds of the former certainly and those of the latter almost certainly, belong to an older horizon than those of the Denver or Converse Co. localities; the latter may be considered as the typical locality for the Ceratops beds. All of the dinosaurs from the Judith River country are smaller, less specialized forms than those from the Converse Co. and Denver localities, as has already been observed by Marsh.

Marsh's statements that the Ceratops beds are below the uppermost beds referred to the Laramie and that they rest upon

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