Chap. II. THEIK MANNER OF PEEHENSION. 57 



seen on one occasion, when a large worm 

 lying beneath a flaccid cabbage leaf tried to 

 drag it away ; for tlie surface of the leaf 

 directly over the end of the worm's body 

 became deeply pitted. On another occasion 

 a worm suddenly lost its hold on a flat leaf; 

 and the anterior end of the body was momen- 

 tarily seen to be cup-formed. "Worms can 

 attach themselves to an object beneath water 

 in the same manner; and I saw one thus 

 dragging away a submerged slice of an 

 onion-bulb. 



The edges of fresh or nearly fresh leaves 

 affixed to the ground were often nibbled by 

 the worms ; and sometimes the epidermis and 

 all the parenchyma on one side was gnawed 

 completely away over a considerable space ; 

 the epidermis alone on the opposite side 

 being left quite clean. The veins were 

 never touched, and leaves were thus some- 

 times partly converted into skeletons. As 

 worms have no teeth and as their mouths 

 consist of very soft tissue, it may be pre- 

 sumed that they consume by means of suction 

 the edges and the parenchyma of fresh 

 leaves, after they have been softened by the 



