LORQUINIA 
27 
living snakes, and by placing near the snakes various animals, the 
student may accurately state that the snake eats certain ones. 
The first of these three methods is open to the objection that, 
in ascertaining what has been eaten, the observer learns little or 
nothing of the psychological behavior of the snake or of the manner 
in which the food is obtained. 
In the field it is only rarely that one happens upon a snake in the 
act of consuming a meal, so that the field observations of a snake's 
feeding habits, although sometimes most valuable, are, nevertheless, 
too few as a rule to repay time used for this purpose alone. 
A captive snake, through nervousness, often refuses food that 
he would eat were he at large in familiar surroundings, in suitable 
temperature or in environment otherwise better suited to his needs. 
On the other hand, it is possible often to ascertain more things 
eaten by certain species by observing two or three members of that 
species in captivity, than by dissecting a much larger number. The 
following observations have been made in this way, although a 
combination of the three methods is most satisfactory. 
Among both old and young Pacific Rattlesnakes, a mouse is a 
much relished tid-bit. Other rodents, such as gophers, squirrels, 
kangaroo rats and even small rabbits are eaten by almost all indi- 
viduals of this species that are large enough. Besides rodents, the 
Pacific Rattlesnake is, in youth, very fond of Fence Lizards {Sceio- 
porus), and I have had as many as three in succession eaten by one 
small rattler. The adults do not seem to relish lizards as do the 
younger ones, and neither old nor young have ever harmed an xMli- 
gator Lizard {Gerrhonotiis scincicauda) or a Brown-shouldered 
Swift (Ufa stansburiana) in my collection. A few bats of an un- 
known species were once eaten by some of my rattlesnakes. The 
Pacific Rattlesnake is also fond of certain birds. 
This rattlesnake is not at all particular about his food and is 
perfectly willing, provided that it is food, to waive the question of 
freshness and eat it alive or dead. When the animal to be eaten is 
alive, it is easily swallowed after having been killed by the venom. 
Mr. Virgil Owen believes that the crotaline (rattlesnake venom) acts 
as a digestive fluid and causes such disintegration within the body 
of the victim as to aid the digestive organs in the preparation for 
assimilation of the nutritive elements in the body of the animal eaten. 
