1912] Ditmars: Feeding Habits of Serpents 203 



by appetite. With the prey within striking distance, there is a 

 lunge of the head, the long recurved teeth take firm hold and the rep- 

 tile's body is literally hurled about the victim, until it is covered with 

 the constricting coils. The process of enveloping the quarry with 

 the powerful folds is wonderfully dextrous among the large serpents. 

 It exceeds in speed that of the smaller, colubrine serpents, which are 

 proportionately more active in pursuit. In the feeding of a twenty- 

 foot Python reticulatus involving a vigorous forty-pound pig, the 

 writer noted on several occasions, with a stop watch, that the time 

 consumed from the initial "strike" of the serpent's head, through the 

 dashing of the coils about it and the beginning of actual constriction, 

 to be within two seconds. The snake apparently aims to seize the 

 animal anywhere and the dash to constrict it is to save the reptile 

 injury. Death usually takes place within a minute's time, but dur- 

 ing the animal's struggles the reptile, not infrequently, is severely 

 bitten ; though the only heed to the injury is to constrict more vigor- 

 ously or bring another coil to bear. The writer has observed many 

 of the smaller constricting snakes badly bitten by rats, and has ex- 

 amined freshly-caught specimens with severe scars. 



The habits described in the preceding paragraph are generally 

 typical of the constricting serpents. Their actions in subduing the 

 prey are as characteristic as the injection of a deadly virus by ser- 

 pents with fangs. Between the constrictors and the poisonous 

 snakes, lie the groups of less pronounced feeding habits. The types 

 we have called the semi-constrictors endeavor to subdue the struggles 

 of the prey, by pressing the animal against the ground with a fold of 

 the body while deglutition is proceeding. Snakes of this type feed 

 upon comparatively small prey. Many of them are rodent-eaters; 

 all are swift of gait and hunt openly, and when seizing small crea- 

 tures possessing sharp teeth that might be used in vigorous defense, 

 the reptile displays extreme caution in manipulating the animal with 

 its jaws so as to place it at a disadvantage. By a lateral, pulling 

 movement of the jawbones, these snakes endeavor to overpower 

 their prey in the same fashion as the constrictors, by literally squeez- 

 ing it to death. 



Among those innocuous snakes which have been designated as 

 non-constrictors, we note several characteristics in feeding, which 

 point to radiating phases of specialization. The writer endeavors to 

 point out these characteristics owing to the feeding habits of ser- 

 pents being of particular interest in possibly tracing their develop- 



