1912] Ditmars: Feeding Habits of Serpents 209 



prey, which, if held by the jaws might inflict damage in the death 

 struggles by teeth or claws. Some of the vipers, particularly those 

 which feed upon birds, lizards and batrachians, retain their hold 

 after striking, driving the long fangs deeply into the victim. 



The writer has endeavored to definitely note by observations 

 of captive specimens and snakes in a wild state, whether or not, as 

 has been alleged, the habit of striking the prey and releasing it is but 

 a nervous and abnormal habit displayed by vipers under observations. 

 At the time of writing he is assured that this is true to a slight extent, 

 but that the habit of simply striking the prey is common with wild 

 snakes. Two observations in the south relate to definite notes of 

 the feeding of the large Diamond-Back Rattlesnake, Crotalus ada- 

 manteus. One, a rabbit struck while in the undergrowth, struggled 

 out on a sandy road to die and was followed by the snake, which 

 consumed the rodent; the other, a tame rabbit, bitten while prowling 

 under the foundation of a hut, dashed into a clearing and was later 

 followed by the snake. The writer has noted one observation of a 

 wild Timber Rattlesnake, Crotalus horridus and a young chipmunk. 

 In the latter instance the chipmunk ran fully twelve feet before 

 overpowered by the poison and died under a flat stone. Immediately 

 after biting the animal, the snake started leisurely in the direction 

 whence it ran and located the quarry without difficulty. In con- 

 trast to the habit, the writer has observed a wild rattlesnake of rather 

 small size bite and hold a short-tailed mouse. 



The writer believes that the viperine snake displays a consider- 

 able amount of caution in the treatment of its prey. These exces- 

 sively nervous snakes are also liable to mislead the observer in 

 tracing normal habits, when the reptiles are studied in captivity. 

 There is little doubt that the jaws retain their hold upon more help- 

 less prey if the snake is feeding in its natural environment. Alert, 

 and always anticipating danger as a captive, the reptile under such 

 conditions strikes and immediately frees the fangs in order to be on 

 the defensive. These theories appear plausible when we note the con- 

 trasting habits of the very nervous rattlesnakes (Crotalus), and the 

 more phlegmatic moccasin and copperhead snakes (Ancistrodon) . 

 The former, as captives usually strike all anim^als offered as food ; 

 the latter seize all prey and hold it unless it be of the larger rodent 

 type that is liable to injure the snake. Among a number of rattle- 

 snakes of different species reared in captivity and consequently far 

 less nervous than those caught wild, the tendency was to strike and 



