Page:Notice of Gigantic Horned Dinosauria from the Cretaceous.pdf/2

174 The lower jaws are massive, and were united in front by a strong pre-dentary bone. This is pointed anteriorly, and its surface marked by vascular impressions, showing that it was covered with horn, and fitted to meet the beak above.

The skull appears to have been at least two metres in length, aside from the horny beak. It represents a genus distinct from the type of the family, which may be called Triceratops. This interesting specimen, which has recently been received at the Yale Museum, was discovered by Mr. Charles A. Guernsey and Mr. E. B. Wilson, in the Laramie formation of Wyoming.

A second specimen of still greater dimensions has since been found at another locality of the same formation, by Mr. J. B. Hatcher. The skull, lower jaws, and a considerable portion of the skeleton, were found together. A striking peculiarity of this skull is the occipital crest, which extends upward and backward, like an open fan. Its margin was armed with a row of horny spikes, supported by separate ossifications, some of which were found in position.

The skull as it lay in the rock measured more than six feet in length, four feet in width, and the horn-cores about three feet in height. These dimensions far surpass any of the Dinosauria hitherto known, and indicate to some extent the wonderful development these reptiles attained before their extinction at the close of the Cretaceous.

A much smaller species is represented by various remains probably from the same horizon, in Colorado. In this species, the nasal horn-core is especially characteristic. It is compressed longitudinally, and its apex is pointed, and directed well forward. It is on the extremity of the nasals, and is thoroughly coössified with them. In front, at the base, it shows indications of union with the premaxillaries, but this connection was slight.

The type specimen was found in Colorado, by Mr. G. H. Eldridge, of the U. S. Geological Survey. The known remains indicate an animal about twenty-five feet in length.

The bison-like horn-cores figured in this journal (vol. xxxiv, p. 324), probably belong to a member of this group, as already suggested by the writer. They were sent to him from a locality in which he had himself collected Mastodon remains and other Pliocene fossils. As they agreed in all anatomical