JOURNAL OF ANIMAL BEHAVIOR 



Vol. 1. SEPTEMBER-OCTOBER, 1911. No. 5. 



HABIT FORMATION IN FROGS 



t 



ASA A. SCHAEFFER 



University of Tennessee 



One figure 



While investigating feeding reactions in frogs, especially with 

 regard to the basis upon which discrimination is made, I in- 

 cidentally made some observations bearing upon habit formation 

 in these animals that contribute to a better understanding 

 of their mental powers. It has seemed to me most satisfactory 

 to incorporate these results in a separate paper instead of making 

 them a part of an investigation on general feeding reactions in 

 frogs, inasmuch as my results on habit formation differ some- 

 what from those obtained by Yerkes and others. As we shall 

 see later, the difference is due to the fact that the feeding in- 

 stinct seems to be more amenable to rapid habit formation than 

 the instinct upon which Yerkes based his experiments. 



The work was carried on at two different places. The first 

 set of observations was made at Cold Spring Harbor, Long 

 Island, and the second set at Knoxville, Tennessee. Four 

 frogs were experimented on at Cold Spring Harbor, i. An 

 adult female Rana sylvatica Le Conte. 2. A Rana virescens 

 Kalm, of uncertain sex, about three-quarters grown. 3. A 

 female Rana clamata Daudin, about three-quarters grown, 

 designated in the observations as " medium." 4. A male Rana 

 clamata, about one-quarter grown, designated as "small." 

 The R. sylvatica was caught at Gilbert, Pennsylvania; the other 

 three were caught at Cold Spring Harbor. 



All these frogs were kept in a single cage about 30 by 30 by 40 

 cm., made of galvanized sheet-iron and fly screening. Into the 

 cage was placed a berry dish about 25 cm. in diameter, in which 

 were placed some pebbles, a large stone, and about a liter of 



