0. C. Marsh—New Tertiary Reptiles. 307 
Measurements. 
Length of frontals on median line, lg 
Width between orbits, 19°5 
idth at posterior margin, 32°4 
Transverse diameter of distal end of humerus,....----- 18°4 
The specimen here described is from Grizzly Buttes, Wyo- 
ming, and was found by Mr. J. F. Page. 
Oreosaurus lentus, sp. nov. 
emarginate. The chevrons are thus attached on either side to 
a prominent ridge, their position being a little behind the 
middle of the centrum. The reptile represented by the remains 
preserved was apparently about two or three feet long. 
Measurements. 
Length of anterior caudal vertebra on lower surface,..... We etirris 
Transverse diameter of articular cup,.......+..2se00e+0: 44 
meen! Alanister, 02. ci as aE ce 
Distance from chevrons to end of ball,..... ..---+-se+05 3°5 
_ The known remains of this species were found by the writer, 
in September last, near Henry’s Fork, Wyoming. 
Oreosaurus gracilis, sp. Nov. 
A somewhat smaller lizard, which may for the present be 
e Or 
Space occupied by the fourteen anterior teeth of lower jaw, 10°2™™- 
375 
Depth of jaw below fourteenth tooth, .......-.-.++-+++ 
Thic ess of jaw at this point,......-.-+-6-eeeeeeeeee 2°4 
Length of symphysis,........- i aeenacs (54 ence 2 
The remains on which this species is based were found, last 
autumn, by the writer, near Henry’s Fork, Wyoming. The 
Seological horizon is Eocene. 
