Chap. II. THEIR INTELLIGENCE. 73 



by worms into their burrows, though not to a 

 great depth ; of these 66 per cent, had been 

 drawn in by the base or foot-stalk ; and 34 

 per cent, by the tip. In this case, therefore, 

 the worms judged with a considerable degree 

 of correctness how best to draw the withered 

 leaves of this foreign plant into their burrows ; 

 notwithstanding that they had to depart from 

 their usual habit of avoiding the foot-stalk. 



On the gravel-walks in my garden a very 

 large number of leaves of three species of 

 Pinus (P. austriaca, nigricans and sylvestris) 

 are regularly drawn into the mouths of worm- 

 burrows. These leaves consist of two so-called 

 needles, which are of considerable length in the 

 two first and short in the last named species, 

 and are united to a common base : and it is by 

 this part that they are almost invariably drawn 

 into the burrows. I have seen only two or 

 at most three exceptions to this rule with 

 worms in a state of nature. As the sharply 

 pointed needles diverge a little, and as several 

 leaves are drawn into the same burrow, each 

 tuft forms a perfect chevaux de frise. On two 

 occasions many of these tufts were pulled up 

 in the evening, but by the following morning 

 fresh leaves had been pulled in, and the 



