FEEDING REACTIONS OF AMBYSTOMA 59 
mals, but suggests that the finding of food on the bottom de- 
pends primarily on the olfactory sense. 
An attempt was now made to compare the reactions of these 
animals to food and odorless inedible objects when the differ- 
ence between them could not be detected by the sense of sight. 
Two packets of gauze, one of which contained raw meat, the 
other cotton, were suspended in the water a few inches apart. 
During the first interval of ten minutes the packet containing 
the meat was approached and seized or nibbled 17 times; the 
packet containing the cotton was approached 11 times, but was 
not seized or nibbled. During a second ten minute interval the 
packet containing the meat was seized or nibbled 21 times, but 
the packet containing the cotton was approached a few times, 
but was not seized or nibbled. Two packets, each of which 
contained only cotton, were now suspended in the water for ten 
minutes. The animals paid little attention to them. They 
were approached a few times but neither of them was seized 
or nibbled. The responses elicited by the packets containing 
raw meat and cotton, respectively, indicate quite clearly 
that while, under the conditions of the experiment, sight 
played the more important part in the approaching reaction, the 
seizing reaction was determined primarily by the olfactory 
sense except when it followed the approaching reaction more 
or less spontaneously. 
In order to eliminate the sense of sight five animals, all of 
which manifested hunger, were subjected to an operation in 
which the eyes were destroyed. One hour later they all seized 
and ate crayfish’s meat which was held before them. They 
were then placed in a circular aquarium 10 inches in diameter 
containing water 3 inches in depth. Crayfish’s meat was dropped 
on the bottom at the center of the aquarium and the time 
which elapsed until it was seized was recorded. Ten trials 
resulted in an average interval of 84 seconds. On the follow- 
ing day crayfish’s meat was again dropped on the bottom of the 
aquarium in the same manner. In this instance five trials 
resulted in an average interval of 26.4 seconds during which 
the meat lay on the bottom of the aquarium before being seized. 
Five normal animals were now placed in the circular aquar- 
ium and offered crayfish’s meat in the same manner. Five trials 
