180 
POPULAR SCIENCE REVIEW. 
reptile from the Trias of Gough, in the Karoo District of South Africa, which 
he also considered to show strong tendencies towards the Mammalia ; hut 
this species he refers to the Theriodont Reptiles, and hence its approximation 
to the Mammalia would seem to lead in the direction of the Carnivorous 
Marsupials. 
This new type, described by Prof. Owen under the name of JElurosaurus 
felinus, is represented by the skull with the lower jaw, but with the post- 
orbital part broken away. There is a single nasal opening (mononarial) ; the 
alveolar border of the upper jaw is slightly sinuous, concave above the in- 
cisors, convex above the canines and molars, and then straight to beneath 
the orbits. The alveolar border of the mandible is concealed by the over- 
lapping teeth of the upper jaw ; its symphysis is deep, slanting backward, 
and destitute of any trace of suture ; the length of the mandible is inches, 
which was probably the length of the skull. The incisors are - — -, and the 
g 5 g g ® 5 
molars probably — - or all more or less laniariform. The length of the 
exserted crown of the upper canine is 12 millims. ; the root of the left upper 
canine was found to be twice this length, extending upwards and backwards, 
slightly expanded, and then a little narrowed to the open end of the pulp- 
cavity. There is no trace of a successional canine ; but the condition of the 
pulp-cavity and petrified pulp would seem to indicate renewal of the working- 
part of the canine by continuous growth. The author infers that the animal 
was monophyodont. JElurosaurus was said to be most nearly allied to Lyco- 
saurus, but its incisor formula is Dasyurine. 
With regard to the characters of the Theriodontia, the author remarked 
that we may now add to those given in his 1 Catalogue of South African 
fossil Reptiles,’ that the humerus is perforated by an entepicondylar foramen 
and the dentition monophyodont. 
Some of the opinions expressed by Prof. Owen with regard to these 
Reptiles, especially as to their Mammalian tendency, and the distinctive 
characters of the order Theriodontia, met with some objections from Mr. 
Hulke and Prof. Seeley, but the facts adduced are certainly of much 
interest. 
Batrachians and Reptiles . — Prof. Cope has some remarks ( Amer . Nat., 
August, 1880) upon his genus Cricotus, founded upon specimens obtained 
from a shale of Triassic or Permian age in Illinois, and distinguished from 
the rest of the Stegocephali (Labyrinthodonts) by the complete develop- 
ment of the centra and intercentra of the vertebrae, both of which form 
vertebral bodies, and, in pairs, support single neural arches. No such cha- 
racter has been detected in the recognized divisions of the Stegocephali ; and 
further knowledge of the structure of the genus shows that it is the type of 
a distinct division of that group, which Prof. Cope defines as follows : — 
1 Centra and intercentra subequally developed as vertebral bodies, a single 
neural arch supported by one of each, forming a double body. Chevron bones 
supported only by intercentra. Basioccipital vertebral articulation cuplike, con- 
nected with the first vertebra by an undivided discoid intercentrum.’ Thus 
the peculiarity of the vertebral column in general is continued into the articu- 
lation of the head ; and, instead of the complex atlas of the Ganocephali, 
there is a single body connecting occipital condyle and first vertebra. In all 
