glove'like hands and feet. The common newt, Hke some of the other salaman' 

 ders, eats the skin immediately after it is shed, shaking it vigorously from side to 

 side as it is engulfed. 



Salamanders are chiefly carnivorous, snapping greedily at small moving 

 objects when hungry. The larvae will eat each other, if they are much crowd' 

 ed. Newts do not hesitate to attack small iish, biting at their eyes and fins, 

 and are also clever at extracting frog eggs from the jelly envelopes that baffle 

 almost all other enemies. The terrestrial salamanders feed largely upon earth- 

 worms, snails and insects. 



Most salamanders can be easily kept in captivity, although all but the 

 newts are too shy to be very entertaining. They do well in tilted tanks, with 

 sphagnum or other moss at the water-line, where they usually gather. Most 

 forms require little food if they are kept in a cool, shaded place, a few DrosO' 

 phila or other insects once or twice a week usually sufficing them. Newts and 

 the giant salamanders are greedy feeders, however, and require worms or mor- 

 sels of raw meat every day or two. 



Salamanders are best preserved for scientific purposes by drowning them 

 in strong (70-95%) alcohol and then transferring them, within half an hour, 

 to five per cent formalin. They regain and keep their original plumpness, if so 

 treated. For aid in identification it is advisable to prop their mouths some- 

 what open while they are still flexible. 



While many field and experimental studies have been made, there remain 

 many interesting problems. A few are suggested here. 



Distribution This is especially interesting, since the salamanders seem very 

 poorly equipped for migrations of any great extent and completely barred by 

 salt water and arid land barriers. Yet we find such peculiar distributions as 

 that of Cryptohranchus, confined to the eastern United States, and the form 

 which most closely resembles it, Megalohatrachus, found in China and Japan. 

 E. R. Dunn's introduction to The Salamanders of the Family Plethodontidae 

 contains an excellent critique of the usual criteria for determination of place 

 of origin and paths of dispersal. The study of local distribution also affords a 

 good lesson in adaptation. Most localities within the United States harbor 

 several genera of salamanders, each usually so well fitted to its particular type 

 of habitat that it comes into little or no competition with the others. Brook, 

 river, pond, lake and forest each have their forms, some well adjusted to live 

 their whole lives in one area, others still making somewhat of a pilgrimage to 

 find different conditions in which their larvae can develop. 

 Life Histories Much remains to be discovered about the life histories of 

 many of our salamanders. Where and under what conditions do they hiber- 

 nate? How long does it take them to reach maturity? What factors govern 

 their choice of a breeding site? How long does the breeding season last? What 

 is their courtship behavior? Even such an apparently minor question as the 



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