252 ZOOLOGY. 
the entrances of the caves. Its color is a pale reddish white, aud, like the 
fish above mentioned, it is blind, although rudiments of eyes are discover- 
able under the integuments by dissection; differing in this respect from 
the Amblyopsis speleus, or the blind fish, which has not even rudiments of 
eyes. The body is elongated and slender, the head depressed, but the 
muzzle rather broad; the anterior feet are provided with three toes, the 
posterior with two. The gills are well developed, but, unlike the Azolotl, 
the opercular flap is not free, but united to the subjacent integument, so 
that there are simply the two lateral cervical slits or fissures. It in fact 
presents a magnified and quite striking likeness to the larva of the 
American Spelerpes longicauda, with the exception of the adnate oper- 
cular flap. The fish-like character is also exhibited in the biconcave 
vertebra, which, however, may be produced by the drying up in the 
prepared skeleton of the gelatinous bulb which constitutes the convex 
articulation of the higher larve. It is highly probable that Proteus is 
ovo-viviparous, although the fact has not been distinctly ascertained. 
Closely related to the Proteus is the genus INecturus, peculiar to North 
America. The form of this genus is stouter than that of the last, and 
there are four toes to each foot. Of the three species known, the first, NV. 
lateralis (pl. 88, fig. 2), 1s an inhabitant of the Mississippi, and the great 
lakes, Superior, Huron, Michigan, Erie, and Ontario; the second, N.. 
maculatus, lives in Lakes George and Champlain; while the third, JN. 
punctatus, and differing from the others by its uniform markings, is an 
inhabitant of the Santee River, South Carolina. In common with the 
Menopoma, they are termed “alligator,” in the central portion of the 
United States; ‘salamander’ or “ water-puppy”’ in some other districts. 
The genus Siren is also an inhabitant of the United States, being 
confined, however, to its southern portion. Here, with the external gills 
of less development than in the preceding genera, the hind legs are 
entirely wanting, the two anterior being provided with four toes each. 
The lungs in this genus play a more important part than in the last; the 
animal, when in full activity, being obliged to communicate occasionally 
with the air. One species, S. dacertina (pl. 88, fig. 1), attains to a 
considerable size, and although having the reputation of being venomous, is 
perfectly free from any power of offence. It is probable that the fossil 
genus Orthophya, from Cxningen, belongs to this family. 
The family of living Menopomide, like that of the Proteide, is, with a 
single exception, confined to North America. The branchize, which are 
found to exist permanently in the preceding family, here disappear after a 
certain length of time, leaving a simple perforation on each side of the 
neck. This, however, is closed up in the genus Megalobatrachus, from 
Japan. The genus Amphiuma is known by the anguilliform body, rudi- 
mentary feet, and pointed head with two parallel series of teeth in the 
upper jaw. Of the two species known, one having two-toed feet is found 
cenerally in the Southern States; the other, with three toes, occurs in the 
southern part of the Mississippi valley. Menopoma has a stout, flattened 
body, broad and much depressed head, eyes very minute, skin corrugated 
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