64 Life and Immortality. 



their base or footstalk. Leaves of other plants, and also 

 the petioles of some compound plants, as well as triangular 

 bits of paper, dry and damp, were experimented with, and 

 the manner of seizing the objects and bearing them into 

 their burrows were as amusing as they were novel and 

 interesting. The leaves and stems used were such as 

 the worms had not been accustomed to in their respective 

 haunts. 



When the several cases experimented on are considered, 

 one can hardly escape from the conclusion that some degree 

 of intelligence is shown by worms in plugging up their bur- 

 rows. Each particular object is seized in too uniform a 

 manner, and from causes which we can generally under- 

 stand, for the result to be attributed to mere chance. That 

 every object has not been drawn in by its pointed end may 

 be accounted for by labor having been saved by some being 

 carried in by their broader ends. There is no doubt that 

 worms are governed by instinct in plugging up their bur- 

 rows, and it might be expected that they would have been 

 taught in every particular instance how to act independently 

 of intelligence. It is very difficult to judge when intelli- 

 gence comes into play. The actions of animals, appearing 

 due to intelligence, may be performed through inherited 

 habit without any intelligence, although aboriginally acquired, 

 or the habit may be acquired through the preservation and 

 inheritance of some other action, and in the latter case the 

 new habit will have been acquired independently of intelli- 

 gence throughout the entire course of its development. 

 There is no a priori improbability in worms having acquired 

 special instincts through either of these two latter means. 

 Nevertheless it is incredible that instincts should have been 

 developed in reference to objects, such as the leaves and 

 petioles of foreign plants, wholly unknown to the progeni- 

 tors of the worms which have acted in the manner just 

 described. Nor are their actions so unvarying or inevitable 

 as are most true instincts. 



