Merriam—feptilian Remains from the Triassic. 57 
Owing to paucity of material it is hardly possible to deter- 
mine with certainty the exact affinities of the species described 
above, so much, however, is certain, viz: that its systematic 
position falls within the limits of the old order, Enaliosauria, 
which has perhaps not altogether outlived its usefulness. 
The majority of the characters, such as extreme shortness 
of centra, high degree of biconcavity of vertebra, small 
zygapophyses, character of articulation of neurapophyses, and 
form of coracoid indicate ichthyosaurian affinities. Some of 
these characters, however, are also found occasionally in the 
Sauropterygia, while heavy, ungrooved, single headed ribs are 
characteristic of this order and do not occur in the /cehthyosauria. 
As no genus heretofore described contains this assemblage of 
characters the new generic and specific name Shastasaurus 
pacificus is proposed for this form. 
The second and smaller individual is represented by about 
twenty-five vertebree, mostly anterior caudals. As the whole 
series measures only 200™™ long the animal was many times 
smaller than S. pacificus. In the characters of the vertebree 
alone there is nothing which would separate this species from 
Ichthyosaurus, but an ungrooved, single headed rib belonging 
to the anterior or middle dorsal region indicates shastasaurian 
affinities. This specimen probably represents a form different 
from that described above, but the material at hand is insuffi- 
cient for specific characterization. 
University of California, Berkeley, May, 1895. 
