Chap. IL THEIR INTELLIGENCr. 75 



leaves were given to worms kept in pots in a 

 warm room, and here the result was dififerent ; 

 for out of 42 leaves drawn into the burrows, 

 no less than 16 were drawn in by the tips 

 of the needles. These worms, however, 

 worked in a careless or slovenly manner ; 

 for the leaves were often drawn in to only 

 a small depth ; sometimes they were merely 

 heaped over the mouths of the burrows, and 

 sometimes none were drawn in. I believe 

 that this carelessness may be accounted for 

 by the air of the room being warm, and the 

 worms consequently not being anxious to plug 

 up their holes eifectually. Pots tenanted 

 by worms and covered with a net which 

 allowed the entrance of cold air, were left, 

 out of doors for several nights, and now 72 

 leaves were all properly drawn in by their 

 bases. 



It might perhaps be inferred from the facts 

 as yet given, that worms somehow gain a 

 general notion of the shape or structure of 

 pine leaves, and perceive that it is necessary 

 for them to seize the base where the two 

 needles are conjoined. But the following 

 cases make this more than doubtful. The 



