No. 373.] LIFE HISTORIES OF CERTAIN SNAKES. 23 
long as the object is moving; but I hardly think there is enough 
comprehension to distinguish a rat or frog as long as they will 
keep perfectly still. I have noticed that a snake will follow its 
victim around and around with its eyes, but, even if it should 
stop suddenly right in front of the snake and in convenient 
distance to strike, and keep perfectly motionless, the snake 
appears to be in doubt of its identity; the slightest muscular 
twitching in the victim, however, is then of course sufficient to 
overcome the uncertainty and hesitancy of the snake. 
Smell is imperfectly developed, but it is amply supplemented 
by their exquisite feeling in the ends of the tongue. The 
sensitiveness of that organ is so fine that an absolute touch 
does not seem to be necessary, but the impression is conveyed 
to quite a long distance, sometimes for an inch or two. In 
regard to hearing, it is rather difficult to obtain accurate 
knowledge. At times it appears very acute, and at others no 
attention whatsoever is paid to sounds. If snakes are very alert 
and some noise is made, without disturbing the cage in the 
least and without making oneself visible, I found that they 
would catch up the sound waves very readily, and conveyed the 
fact by turning their-head quickly in the direction of the sound 
and by their rapid display of the tongue. 
The most careful and thorough observations, however, have 
so far not brought me to the solution of that bugbear of herpe- 
tologists, the use of the pit of the Crotalidz and their next, of 
kin, the moccasins. The assumption of the existence of a 
sixth sense is certainly easily maintained by the anatomical 
structure of the pit and the ramifications of the nerve in its 
linings. i 
On the life of some of our venomous snakes in captivity a 
few remarks may not be out of place. It is generally believed 
that they refuse food persistently and finally die of starvation. 
I have found, however, that the majority will accept living food. 
without hesitation, as long as their receptacle is in any way 
arranged like their native haunts. The most interesting of our 
venomous ophidians I consider the copperhead, which in cap- 
tivity becomes very tame, learning to take food, such as pieces 
of meat and fish, from the fingers. I possessed one some time 
