.100 HABITS OP WORMS. CHAP. II. 



To sum up, as chance does not determine 

 the manner in which objects are drawn into 

 the burrows, and as the existence of special- 

 ized instincts for each particular case cannot 

 be admitted, the first and most natural sup- 

 position is that worms try all methods until 

 they at last succeed ; but many appearances 

 are opposed to such a supposition. One 

 alternative alone is left, namely, that worms, 

 although standing low in the scale of organiz- 

 ation, possess some degree of intelligence. 

 This will strike every one as very impro- 

 bable ; but it may be doubted whether we 

 know enough about the nervous system of 

 the lower animals to justify our natural dis- 

 trust of such a conclusion. With respect to 

 the small size of the cerebral ganglia, we 

 should remember what a mass of inherited 

 knowledge, with some power of adapting 

 means to an end, is crowded into the minute 

 brain of a worker-ant. 



Means by which icorms excavate their 

 burrows. This is effected in two ways ; by 

 pushing away the earth on all sides, and by 

 swallowing it. In the former case, the worm 

 inserts the stretched out and attenuated 



