MUD PUPPY, WATER DOG, OR DOG FISH. 715 
one of these animals caught in the Hudson. He also informed me that 
one had previously been captured in that river. It had probably passed 
thence through the Erie canal or the one connecting the river with 
Lake Champlain. 
Kneeland* atates that this animal is nocturnal, feeds upon living 
worms, never dead ones unless very hungry, swallowed but could not 
digest minnows two and half inches long, has its giils nibbled off by 
small fish, and hence can survive by cutaneous and pulmonary respira- 
tion. Smith ¢ confirms Kneeland’s view of the pulmonary, as well as 
branchial respiration, in that he succeeded in inflating one of the pul- 
monary sacs. He also found a Libellula larva in the animal’s stomach. 
Their motions are very active when in the water, and are performed by 
the body and tail. They seem to be ill at ease when placed in the sun, 
and attempt to get out by retiring into a shady part. They have been 
known to live in water that froze a half inch every night for three 
months, but died in about four hours when removed from the liquid. 
When in water they may be observed crawling about over the bottom, 
rising to the surface at times and expelling a globule of air or effecting 
the same under water. They eat a numberof worms a day, or go several 
months without food. At times they are found with parasitic worms 
near their gills. The flesh of this animal is said to be excellent eating. 
SUB-ORPER CADUCIBRANCHIATA. 
Branchia not present in the adult state; maxillary and nasal bones large; prefrontals 
usnally present ; premaxille separate or anchylosed, and always dentigerous. 
*Branchial apertures upon the neck open. (DEROTREMATA) 4a. 
*Branchial apertures closed in aduit. 0b. 
@. Anterior metacarpal bones three; extralimital. ; a . AMPHIUMIDZ. 
@. Anterior metacarpals four. - C z - : - . MENOPOMIDA. 
b. Anterior metacarpals four. . - - ; . : . SALAMANDRIDZ, 
FAMILY MENOPOMIDA. THE MENOPOMES. 
Protonopside, COPE. 
Skull broad ; parasphenoid edentulous; vomer with teeth along its anterior margin; 
premaxill~e aud dentaries dentigerous; maxilla and nasals large; pterygoid present 
and very broad; twe separate premaxillary bones; prefrontals and parietals prolonged 
80 a8 to embrace the frontals; fronto-temporal arch absent; occipital condyles sessile ; 
basihyal cartilage present ; gill holes open or closed ; branchial arches may be reduced 
to two; upper and lower eyelids distinct ; vertebra amphicelous; carpus and tarsus 
* Proc. Bost. Soc. Nat. Hist., vol. vi, pp. 152, 371, and 429. 
+ Ann. Lye. Nat. Hist., N. Y., vol. ii, p. 259. 
