330 O. C. Marsh—The Order Theropoda. 
The specimen of Ceratosaurus here first described presents 
several characters not hitherto seen in the Dinosawria. One 
of these is a large horn on the skull; another is a new type of 
vertebra, as strange as it is unexpected ; and a third is seen in 
the pelvis, which has the bones all codssitied, as in existing 
Birds. Archwopteryx alone among adult birds has the pelvie 
bones separate, and this specimen of Ceratosaurus is the first 
Dinosaur found with all the pelvic bones anchylosed. Another 
feature of this skeleton, not before seen in the Theropoda, is 
the presence of osseous dermal plates. These extend from the 
base of the skull along the neck, over the vertebre. The plates 
appear to be ossitied cartilage. | 
his interesting fossil is quite distinct from any hitherto 
described, and, as it represents a new genus and species, may 
be called Ceratosaurus nasicornis. It also belongs to a new 
family, which may be named the Ceratosauride. 
he skeleton, which is almost perfect, is over seventeen feet 
in length by actual measurement. The animal when alive 
was about half the bulk of the species named by the writer 
Allosaurus fragilis, which is from the same geological horizon. — 
A second skeleton, some parts of which, also, are here described, 
is referred to the latter species. | 
THE SKULL. 
antorbital 
A fifth : 
characteristic of the y Ef her da, and are found also in the a 
