O. C. Marsh—New Jurassic Reptiles. 505 
the walls are reduced to a thin shell. There are apparently no 
partitions across their cavity, and the inner surface of the walls 
is quite smooth. The anterior caudal vertebra, at least, have 
essentially the same character. The trunk vertebree preserved 
are elongate, biconcave, with high neural arches, united to the 
centra by suture. The sides of the vertebrae are somewhat 
excavated, and the openings into the cavity are allsmall. The 
cup at each end of the centra is unusually smooth, and regular. 
The zygapophyses are near together, and stand nearly vertical. 
The following measurements will indicate the size of this 
anim 
Leneoth of centrum of lumbar vertebra ..-- -------- 35mm 
Transverse diameter of anterior face of centrum.-.- 19° 
ertical diameter o.oo ee en cee tenes 21° 
Least transverse diameter of centrum --.-..---.--- 10° 
Least thickness of walls of centram ....-....------ 1? 
Length of anterior caudal -----.----------------- 33° 
Transverse diameter of anterior face -------------- 5 be 
Thickness of walls of centrum, near middle ---.---- 1° 
Least transverse diameter of centrum ---.------.-- 10° 
The known remains of this species indicate an animal about 
as large as a wolf, and probably carnivorous. 
Yale College, New Haven, November 18, 1879. 
