SIRENIDA, — XCVIL 175 
Orpver XXIV. TRACHYSTOMATA. 
This order contains a single family. (rpaxvs, rough ; oréua, mouth.) 
Famity XCVII. SIRENIDAS. (THe Sirens.) 
Body elongated, eel-like, with no posterior limbs, not even a 
vestige of pelvis; head flattened; snout obtuse; mouth narrow, 
jaws with horny sheaths; floor of mouth with teeth or asperities; 
vomer with two large patches; eye very small; lips thick; tail com- 
pressed, finned. Genera 2; species 2, Pseudobranchus striatus 
(LeC.), of Georgia, a small species with 3 toes and with thickened, 
functionless gills, and the following :— 
a, Gills large, bushy, in function throughout life; toes 4; spiracles 3. 
Siren, 250, 
250. SIREN Linnzus. 
488. S. lacertina L. Mup Ee. Tail shorter than body, 
pointed at tip. Blackish, sometimes dotted. L. 36. Lowland 
streams and swamps, N. Ind. to N. C. and S. (Lat., like a 
lizard.) 
OrpER XXV. PROTEIDA. 
This order contains a single family. 
Famity XCVIII. PROTHIDAS. (Tue Mup Purrtss.) 
Salamanders provided with bushy external gills, and having the 
branchial clefts remaining open through life; teeth well developed; 
limbs 4. Genera 2; species 3 or 4. Proteus inhabits caves in S. 
W. Austria, and Necturus the fresh waters of the U.S. Proteus 
is blind, nearly colorless, and has the toes 3-2. 
a. Toes 4-4; tongue large, free in front; vomerine teeth in one strong series; 
eyes small, not covered. . . - « + « « - + « Necrurus, 251. 
251. NECTURUS Rafinesque (1819). (Menobranchus Harlan, _ | 
~~ 1825.) (vnxrns, a swimmer; ovpd, tail.) 
489. N. maculosus Rafinesque. Mup Puppy. (N.) WATER 
Dog. (S.) Brown, more or less spotted; young with traces of a 
lateral band; gills large and bushy, bright red, forming 3 tufts on 
each side; a strong fold across throat ; head broad, depressed ; tail 
much compressed. E. U. S., chiefly N. and W. of the Alleghanies, 
abundant in the Great Lake Region. L. 24. (Lat., spotted.) 
Orpver XXVI. URODELA. (THE SAaLamMAnDERS.) 
Body naked, elongate, subterete; both jaws with teeth; 4 limbs 
present (wanting in the tropical family Ceciliide); tail persistent 
through life; no external gills in the normally developed adult. 
