FOSSIL VERTEBRATES —REPTILIA 517 
b 
The same 
form was afterwards described as fish and as a lizard, until finally 
to it the name ‘‘homo diluvii testis et theoscopos.’ 
its true nature was made out. The form reached a length of 
about four feet in the largest specimens and was one of the 
largest of the Caudata. In most of its skeletal characters it was 
very similar to the modern J/enobranchus. 
Megalotriton is one of the Salamandrina from the Upper 
Eocene of France. It was of considerable size, judging from 
the vertebre and the detached bones of the limbs. No com- 
plete skeleton has been found. 
The Anura (Ecaudata) are little known from the fossil forms. 
They appear in the Tertiary with almost as many genera and 
species as at the present time, and there has been little change 
in the forms. 
The origin of the modern forms of the amphibians is not 
known. Zittel says of these forms that they can in no sense be 
derived from the labyrinthodonts, for between these and the 
modern forms there exists not only a great morphological gap, 
but a great break in the geological record as well. 
Ras Pane AC 
PAREIASAURIA.—The simplest of the Reptlza differ very little 
from the Ampiibia. There is little in the structure of the 
Pareiasauria that might not belong to the Labyrinthodontia except 
the arrangement of the bones forming the base of the skull. 
Add to this that the animal did not undergo a metamorphosis from 
a water toa land form and the list of differences is complete. All 
during the Carboniferous time the conditions had been growing 
better and better fitted for the existence of purely terrestrial, 
air-breathing forms, and at the end of that time, if not, as there 
is reason to think, some time before, there appeared the fore- 
runners of the great tribe of reptiles. As has been indicated, 
the Microsauria were in all probability the direct ancestors of 
the reptiles, but the evidence of the preserved forms is so 
incomplete that we do not have either what must have been the 
