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frogs, toads, newts, and salamanders, a complete metamor¬ 
phosis takes place, the gills of the immature animal disappear¬ 
ing altogether in the adult. In the genus Menopoma the gills 
become reduced to a small orifice in the side of the neck, and 
the lungs are well developed. 
Of the batrachians, the Siren ( Siren lacertina ), the Am- 
phiuma (. Amphiuma means), and the Proteus ( Menobranchus 
maculatus ), are usually in the collection. The two former 
are found in the soft mud of streams and ditches from Geor¬ 
gia southward. The specimens in the Garden rarely come 
out of the mud, except to get the worms on which they 
principally live. The Menobranchus or Proteus is from the 
fresh-water streams and lakes of the Middle States, and feeds 
upon worms, grubs, and larvae. 
The Hell Bender or Mud Devil (. Menopoma alleghenien- 
sis) is found in the river mud of all tributaries of the Missis¬ 
sippi, and occasionally in other localities in the Gulf States. 
The salamanders and tritons, or newts, are found plenti¬ 
fully all over the United States. Many of them live entirely 
in the water, except at the breeding season. The Red- 
backed Salamander (. Plethodon cinereus erythronotus), the 
Two-lined Salamander ( Spelerpes bi-lineatus), the Red Sala¬ 
mander (Spelerpes ruber), and the Black Newt, ( Desmog - 
nathus nigra), are among the most common species. 
A number of curious batrachians ( Amblystoma mavottium ), 
from the elevated plateaus in the western United States, will 
be found in the vivarium. Near them are several specimens 
of their larval form, with large gill tufts and a crest along 
the spine and tail. These shrink up and disappear when the 
animal becomes mature. 
The toads and frogs have a range co-extensive with the 
salamanders. The Common Toad (. Bufo leniiginosus) being 
found all over North America, with a number of well-marked 
varieties. 
The best known of the frogs are the Bull Frog ( Rana 
catesbiana), the Swamp Frog ( Rana palustris), the Brook 
Frog (Rana clamitans), and the Shad Frog (Rana halecina). 
The North American fauna possesses a large and varied num¬ 
ber of serpents (Ophidia), members of which order are found 
all over the world. The only venomous snakes belonging to 
North America are the different varieties of the Rattlesnake, 
