A Study of the Food Habits of the Ithacan 



Species of Anura During 



Transformation* 



Philip A. Munz of Pomona College, Claremont, California 



In recent years almost as much interest has been attached to the study of the 

 habits of animals and to the relation to the environment as to the structure and 

 classification. Naturally enough the food-habits are among those that can be most 

 profitably studied; as an example I have to cite only the work of Professor S. A. 

 Forbes of the University of Illinois on the food of fresh-water fishes. His results, 

 embodied in a series of papers published by the Illinois State Laboratory of Natural 

 History, have been very suggestive and an inspiration to investigation in allied 

 groups. When, therefore, a study of the food-habits of various species of the Anura 

 during their transformation period was suggested to me, it was gladly taken as a 

 subject of some promise. 



The purpose of the investigation was to learn something more definite than was 

 alreadv known concerning the food before and after transformation and to see how 

 the change from the one kind to the other came about. It was thought that such 

 knowledge might aid to some extent in frog-culture during this rather critical period 

 of a frog's development. 



The problem was undertaken with the advice and criticism of Doctor A. H. 

 Wright of Cornell University. To him my sincere gratitude is hereby given, not 

 only for his suggestion of the problem and for his help in carrying it out, but for 

 the abundant material which he so generously put at my disposal and which was 

 the result of much careful collecting on his part. 



Largely because of the work he had been doing at Ithaca during the last ten 

 years, material was available for all eight species of Anura occurring in the Cayuga 

 Lake Basin of New York state. In all, 586 specimens were dissected, giving a 

 fairly representative series for each of the species which were as follows: 



Rana catcsbeiana Shaw. The Bullfrog. 



Rana clamitans Latreille. The Green-frog. 



Rana sylvatica Le Conte. The Wood-frog. 



Rana palustris Le Conte. The Pickerel-frog. 



Rana pipiens Schreber. The Leopard- or Meadow-frog. 



llyla crucifer Wied. The Peeper. 



Ilyla versicolor Le Conte. The Tree-toad. 



Biifo americaniis Holbrook. The Common Toad. 



METHODS 

 As specimens were collected in the field they were immediately killed, usually in 

 formalin, in order that digestion would immediately cease. Each lot that was col- 



A contribution from the Zoological Laboratory of Cornell University of Ithaca, New York. 



