INJURING THE LEAVES. 



155 



small, round, yellowish head, with a black dot on 

 each side of it, and are provided with twenty -two^ 

 short legs. The body is green above, paler at the 

 sides, and is soft and almost transparent, like jelly. 

 The skin of the back is transversely wrinkled, and 

 covered with minute elevated points ; and there are 



Fig. 81. Pear-tree Slug : fly and larvae. 



two small, triple-pointed warts on the edge of the 

 first ring, immediately behind the head. These gel- 

 atinous and sluggish creatures eat the upper surface 

 of the leaf in large, irregular patches, leaving the 

 veins and skin beneath untouched ; and they are 

 sometimes so thick that not a leaf on the bushes is 

 spared by them, and the whole foliage looks as if it 

 had been scorched by tire and drops off soon after- 

 wards. They cast their skins several times, leaving 

 them extended and fastened to the leaves ; and after 

 the last moulting they lose their semi-transparent 

 and greenish color, and acquire an opaque, yellowish 

 hue. They then leave the bushes, and burrow an 

 inch or more in the earth, where each one makes for 

 itself a small, oval cell of grains of earth, cemented 

 with a little gummy silk." They remain in these 

 pupa cells until the following season, when they 

 emerge as flies. 



