174 0. C. Marsh — Gigantic Homed Dinosauria. 



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. 



Triceratops flabellatus, sp. no v. 



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. 



Triceratops galeus, sp. nov. 



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 com- 

 pressed longitudinally, and its apex is pointed, and directed 

 well forward. It is on the extremity of the nasals, and is 

 thoroughly coossified 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. II. 

 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 



* This Journal, vol. xxxvii, pp. 334. 



