1871.] 
Length femur..... iw dei, eevee 1 as oes vas 
Proximal diameter dO. ie igs cos ess oe eee ctu c est 
Median i ns ee 
Length centrum dorsal vertebra without 
Transverse diameter cup.............-- 
Vertical < eek ea 
Length of a lumbar (total)..............-- 
Diameter ball do (transverse)..... 
Length caudal........---.-- 
Dept ball Go, io ee ee. 
Width d6, Go... 2.04... beets 
The form of the humerus is something like that of Ichthyosaurus. 
Both this element and the femur are remarkable for their small 
of the elements of' the anterior 
They are scarcely half the dimensions 
limb of Holcodus ictericus, and are even less than those of L. dyspelor in 
proportion to the animal’s size. 
It is unnecessary to compare this species with any but the Liodon pro- 
riger. Of this species, I unfortunately do not possess any of the limb 
rison on vertebree alone. The type spcci- 
bones, and must rely for comp: 
men lacks the dorsals, hence the caudals alone remain for comparison. 
This shows that they are three or four times as large as the same propor- 
y So < 
tions of the Z. crassartus. In a smaller specimen of L. proriger, the 
dorsals are preserved, but so crushed as to be little available for measure- 
ments. One point besides the greater size is noticeable, their generally 
more elongate form, and the distinct superior emargination for the neural 
canal. 
The remains above described were obtained by Professer 
B. F. Mudge, 
near Eagle tail, in Colorado, a few miles west of the line separating that 
Territory from the State of Kansas. 
A series of twenty-nine caudal vertebrae with and without diapophyses, 
from a bluff on Butte Creek belongs perhaps to this species. The proxi- 
mal specimens at least, cannot be distinguished from those of - 
Mudge’s collection. ‘The distal ones cannot readily be distinguisicd from 
the terminal ones of L. proriger. 
LIODON PRORIGER, Cope. 
Proc. Acad. Nat. Sci., 1869, 123. Trans. Am. Philos. Soc., 1870; 202. 
This isthe most abundant of the large species of the Kansas chalk. 
The writer found a muzzle consisting of premaxillary, and portions of 
maxillary and dentary bones, ina spur of the lower blufts of Butte Creek, 
and numerous fragments of cranium and vertebra on a denuded tract in 
the same neighborhood. Both of these belonged to individuals of smaller 
size than the type, the opportunity of examining which I owe to Professor 
Agassiz. The more complete Butte Creek specimen belongs to a huge 
animal; the size is grandly displayed by a complete premaxillary bone 
with its projecting snout, and large fragments of the maxillary. These 
