288 THE CULTIVATION OF THE 



nine-twentieths of an inch long, when fully grown. 

 The head is snnall and of a dark chestnut color, and is 

 concealed under the fore part of the body. They are 

 largest before, and taper behind, and resemble small 

 tadpoles. They swell out the fore part of the body and, 

 rest with the tail a little turned up. They live mostly 

 on the upper side of the pear leaves, and eat the sub- 

 stance, leaving only the veins and the under skin 

 untouched. They may be so numerous as to cover the 

 leaves. The trees thus attacked are forced to throw out 

 new leaves during the hot weather, at the ends of the 

 twigs and branches that still remain alive, and thus use 

 leaf buds that should not have come out until the next 

 spring. Thus the vigor of the trees is exhausted, and 

 as the leaves elaborate the juices of the fruit, the fruit 

 itself must suffer. In twenty-six days these slugs come 

 to their growth and, in this time, cast their skin five 

 times. They eat the first four coats, but never the last, 

 and after they have gone, you see this last skin stretched 

 on the leaf. After this last coat has been shed, the 

 slugs are not slimy, but have a clean yellow skin, and 

 not viscid. 



They change also in form, become longer, and you 

 can see the head and the marks between the rings. 

 Now in a few hours they leave the trees, having crept or 

 fallen to the ground, and a high wind at this time with 

 dry atmosphere, favors them. Now, on the ground they 



