388 Prof. O. C. Marsh—New Jurassic Dinosaur. 
the processes in mammals known as metapophyses, they may bear 
the same general name, being distinguished as the post-metapophyses. 
The term pre-metapophyses should then be applied to the processes 
in mammals. 
The post-metapophyses probably serve for the attachment of liga- 
ments in the place of the neural spine, which is here wholly want- 
ing. These processes, which are at first oblique in position, gradually 
become more vertical and stouter, and coalescing at their bases, 
finally become united throughout, and are thus converted into the 
neural spine. 
Fetal Dinosaurs.— Remains of a very small Dinosaur were found 
in immediate relation with the type specimen of Morosaurus grandis. 
These remains, which consist of a complete femur, the larger portion 
of both humeri, and several vertebrae, show no essential differences 
from the large specimens except in size, and indicate an animal of 
pethaps seven feet in length, and little more than two feet in height. 
The imperfect ossification of these bones indicates that the animal 
was very young, and it seems probable that it was foetal. The only 
other similar case known in the Dinosauria is the apparent embryo 
observed by the writer in Compsognathus.* 
Classification.—The various genera of the Sauropoda, and in fact 
of the Dinosauria in general, cannot at present be distinguished by 
the detached teeth. In one form, however, the teeth are quite pecu- 
liar, and the dentition appears to offer generic characters. The 
maxillary teeth of this form have been referred to Stegosaurus 
(Silliman’s Journal, vol. xix. p. 255, pl. vi. figs. 4 and 5), as they 
were first found in connection with the remains of that genus. 
Later investigations indicate that they belong to the Sauropoda, and 
there is some evidence that they are the teeth of Diplodocus. 
The main characters of the order Sauropoda, and of the two 
families now known to belong to it, are as follows :— 
Order Sauropoda. Herbivorous.—¥eet plantigrade, ungulate ; five 
digits in manus and pes; second row of carpal and tarsal bones un- 
ossified. Pubes projecting in front, and united distally by cartilage ; 
no post pubis. Fore and hind limbs nearly equal ; limb bones solid. 
Sternal bones parial. Premaxillary bones with teeth. Precaudal 
vertebrz hollow. Hach sacral vertebra supports its own transverse 
processes. i 
Family Atlantosauride. Anterior vertebre opisthoccelian. Ischia 
directed downward, with extremities meeting on median line. 
Anterior caudals with lateral cavities. A pituitary canal. 
Family Morosauride. Anterior vertebrae opisthoccelian. Ischia 
directed backward, with sides meeting on A line. Anterior 
caudals solid. Pituitary fossa only. 
1 See Silliman’s Journal, vol. xxii. p. 340, November, 1881. 
