SHORT STUDIES OF BATRACHIANS. 347 



Here the frog remained until morning. The following 

 day I removed the pail, and buried it within fifty yards 

 of a running brook. I then took seven frogs of three 

 species and placed them upon the sieve, which was about 

 half an inch above the surface of the water. Here five 

 of them remained during the whole day, exposed to the 

 glare and heat of a cloudless midsummer day. The 

 evaporation from the water beneath them barely kept 

 them alive ; and yet within so short a distance was a run- 

 ning brook, with all the attractive features of ideal frog- 

 life. 



I repeated this experiment, with slight modifications, 

 several times, and always with essentially the same re- 

 sults. 



Hoping to find that in the pursuit of prey, which is 

 principally insects, frogs would display some intelligence, 

 I tried several experiments to test their ingenuity ; but it 

 was of no avail. Unless the food could be easily reached 

 by making the simple exertion of a single leap, the frogs 

 would go hungry. Subsequently I placed a large fly 

 upon a piece of thin mica, and surrounded it with a circle 

 of fine needles, piercing the plate. The fly thus pro- 

 tected could only be seized by the frog suffering a severe 

 pricking of the jaws. This, I found, a frog would suffer 

 indefinitely, in its attempts to secure the fly. In one in- 

 stance, the frog, which had been fasting for seventy-two 

 hours, continued to snap at the needle-protected fly until 

 it had entirely skinned its upper jaw. I concluded from 

 this that the wits of a frog were too limited to be demon- 

 strated. 



Some weeks after having completed these experi- 

 ments, I had the good fortune to capture two fully 

 grown specimens of the bull- frog (Rana Catesbyana) ; 

 and, noticing their enormously distended sides, I exam- 



