REPTILIA. 253 
into numerous folds, four toes on the anterior, and five on the posterior 
feet. The tail is much compressed, and the soles of the feet margined 
with a fold of skin enabling the animal to move with facility in the water. 
It is known generally as the “alligator,” although, of course, improperly ; 
and spends most of its time in the water, very rarely coming upon land, 
except possibly at night. These animals are exceedingly voracious, feeding 
on insects, fish, and, in some known instances, small mammalia. They 
bite at a baited hook, in the spring and autumn, with as much greediness 
as fishes, and are frequently caught in this way, to the great disappointment 
of the western angler, who, in most cases, is so much afraid of his prize as 
to cut the line rather than risk the danger of contact with so repulsive an 
object. No danger exists, however, as the animal, with his short teeth, is 
unable to produce any injury, even if willing to do so. It sometimes 
attains a large size, as upwards of two feet, although the average is, 
perhaps, twelve or fifteen inches. Little is known of its larval history, 
except that it loses its external gills when only a few inches long. The 
known species are M. alleghaniensis, from the waters of the Mississippi, 
and M. fusca, from those of South Carolina and Georgia. The next, and 
last, living genus of this family is Megalobatrachus, the most gigantic of all 
living Batrachia urodela. It resembles Menopoma closely in appearance, 
the principal difference being found in the entire obliteration of the lateral 
cervical foramen. The single species, M. sieboldtii, inhabits certain ele- 
vated lakes in Japan, where it grows to a great size. One specimen, now 
or recently living in the Museum at Leyden, exceeds three feet in length, 
weighing upwards of eighteen pounds. 
The passage from the Menopoma to Megalobatrachus is to be found in 
a gigantic fossil genus, Andrias, from the fossiliferous marls of Giningen. 
Scheuchzer, who published the first description of the single species, A. 
scheuchzeri, called it Homo diluvii testis ; being impressed with the idea 
that the skeleton obtained was human, and, as he thought, entombed by the 
Noachian deluge. In size it is about equal to that of the Japanese giant, 
from which it differs in having the peculiar structure of the petrous and 
pterygoid bones, as well as the great breadth of the head observed in 
Menopoma. The anterior toes are longer in proportion than in the allied 
genera. 
The sub-order of Atretodera, to which we are led by the genus Megalo- 
batrachus. are without branchial apertures or gills when in the adult state. 
Although there is a great variety of form in this sub-order, yet it is difficult 
to constitute more than one family, that of the Salamandrine. Of the 
three principal regions of the salamanders, Europe, Japan, and North 
America, each is characterized by some peculiarity of structure. Thus 
while most of the European forms have parotid glands, like those of the 
toad, and one at least of the Japanese is provided with temporary claws, 
the American alone have teeth on the sphenoid bone: neither is there any 
vestige of the parotid gland, above referred to, in the latter. 
The salamanders were formerly divided into two great genera, Sala- 
mandra and Triton; the former with rounded tail and terrestrial habits, 
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