180 INSECTS INJURIOUS TO THE PLUM. 



remain until they reach maturity. The larvae do not feed 

 on the leaves, but on pollen, or bee-bread, stored up in their 

 cells by the parent insects. This bee is not very abundant, 

 and is never likely to prove very injurious. It is represented 

 in Fig. 191, with examples of the injury it does. 



No. 93. The Plum-tree Aphis. 



Aphis prunifolii Fitch. 



This aphis resembles in its appearance and habits the apple- 

 tree aphis, No. 57 ; it is, however, much less common. It 

 infests the under side of the plum leaves, puncturing them 

 and sucking their juices, causing them to become wrinkled 

 and twisted. When first hatched, these insects are of a 

 whitish color tinged with green, but as they increase in size 

 they become of a deeper green, and when mature some of 

 them are black, with pale-green abdomens and dusky wings. 

 The remedies given under the apple-tree aphis (No. 57) are 

 equally applicable to this species. 



ATTACKING THE FRUIT, 

 No. 94. The Plum Curculio. 



Conotrachelus nenuphar (Herbst). 



This insect is without doubt the greatest enemy the plum- 

 grower has to contend with, for when allowed to pursue its 

 course unchecked it often destroys the entire crop. The per- 

 fect insect is a beetle belonging to a family known under the 

 several names of curculios, weevils, and snout-beetles. It is a 

 small, rough, grayish or blackish beetle, about one-fifth of an 

 inch long (shown, magnified, at c in Fig. 192), with a black, 

 shining hump on the middle of each wing-case, and behind 

 this a more or less distinct band of a dull ochre-yellow color, 

 with some whitish marks about the middle; the snout is rather 

 short. The female lays her eggs in the young green fruit 



