Newman, Habits of Tortoises. 149 



tortoises combine in a peculiar way the traits of aquatic and ter- 

 restrial forms. Their mock fierceness may be the relic of a fierce 

 ancestry. After the first attempts to escape they become quite 

 docile and cease to resent their captivity. The species presents an 

 odd mixture of traits that could probably be reconciled by a more 

 complete knowledge of its phylogenetic history. 



5. Chelydra serpentina (the Snapping Tortoise^. 



The habits of this species are quite generally known and have 

 been referred to in a more or less fragmentary way by several 

 authors. My observations on the subject are less complete than 

 those given for the preceding species, yet for the sake of com- 

 parison it seems advisable to set down in systematic form the 

 available facts. 



Chelydra seems to appear and disappear along with Graptemys 

 and it is certain that hibernation takes place in the mud of the 

 pools, swamps and streams of the neighborhood. I am informed 

 on reliable authority that it is possible at almost any time in the 

 winter to secure "snappers" from the mud of the stream bottoms 

 by breaking the ice and grappling in the mud with sharp hooks 

 attached to stout poles. 



During the early spring "snappers" frequent the land, leaving 

 the pools probably in search of food. Later in the season, how- 

 ever, they seem to remain constantly in the water, either floating 

 near the surface with the tip of the snout protruded or buried in 

 the mud at the bottom. 



Their nesting season corresponds closely with that of 

 Graptemys. 



Chelydra basks occasionally in the open, but is much more apt 

 to resort to warm shallow waters, where it buries itself in the mud, 

 leaving only the head free. The head is very inconspicuous on 

 account of its dull gray color and rough warty appearance. The 

 young are not so careful about concealing the body with mud. 

 In shallow pools at the margins of swamps they may be seen in 

 considerable numbers, lying exposed to full view. 



Chelydra is a slow and clumsy swimmer, progress through the 

 water being aided as a rule by walking along the bottom. On 

 land they walk slowly, with a peculiarly elephantine gait, yet 

 succeed in covering considerable distances, often going from one 



