68 _ General Notes. [January, 
in some of the pelvic characters we must, according to Baur, 
look to the herbivorous forms for the closest resemblance. The 
cervical vertebra of Ceratosaurus havea very peculiar articulation, 
being deeply concave posteriorly and plane in front, thus prevent- 
ing the reception of the anterior face deeply into the posterior 
face of the centrum in front. The depth of its shallow entrance 
is marked by a ledge on the sides of the anterior face. The skull 
of Ceratosaurus is peculiar, according to Marsh, in the large 
anteorbital opening. 
Professor Marsh separates Ceratosaurus as type of a family 
distinct from the Megalosauride, but it does not appear from his 
diagnosis of the latter on what grounds. The only distinctive 
character given to the former is “ horn on skull,” which is cer- 
tainly of not more than generic value, and may not even be that. 
The skeleton of the Megalosauridz is little known, but it is 
probable that the Ceratosauridz must be distinguished from them 
by the coossified metatarsals and pelvic bones. The other dis- 
tinct family appears from Marsh’s definitions to be the’ Zanclo- 
dontidz, where the cervical vertebra are biconcave, and the pubes 
different. I have elsewhere? referred to Professor Marsh’s tend- 
ency to exaggerate the systematic value of various characters,’ 
and reiterate the opinion that his “orders” are of no higher rank 
than suborders, 
As usual, Professor Marsh omits the customary reference to 
facts already determined by others. Thus he states that some of 
these reptiles probably rested on the free extremities of the 
pelvis in a sitting posture (p. 336). The writer pointed out this 
peculiarity as long ago’as 1870. Professor Marsh also finds 
(p. 337) that the presence of various genera of Dinosaurs, closely 
allied to these American forms, in essentially one horizon in the 
Isle of Wight, suggests that the beds in which they occur are not 
Wealden as generally supposed, but Jurassic. The American 
beds were at first referred to the Wealden by Marsh, and subse- 
quently to the Jurassic by the writer in “ Relations of the Hori- 
zons of Extinct Vertebrata of Europe and North America.” 4 
This paper is well illustrated by six plates.—E. D. Cope. 
Fao Academy Philada., 1883, p. 97, on the structure of the skull in the 
? Another illustration of this is seen in a short article by Professor Marsh imme- 
, a New O i 
n 
ged with those of Saur: 
-clature. 
3 Extinct Batrachia Reptilia and Aves N. America, p. 122 E. 
t Report of the Proceedings Con Ae Fi : 
Terrs, Vol. v. Coe cacloge, Paris; Bulletin U, S. Geol. Surv. 
