INSECTS INJURIOUS TO STONE FRUITS 



661 



The Plum Gouger * 



This is a native species which breeds upon wild plums and is 

 most injurious to native varieties. It is common throughout 

 the Mississippi Valley, but seems to be most injurious westward 

 and occurs in Colorado. The work of the beetles might be easily 

 mistaken for that of the curculio (p. 576). The adult beetle is 

 readily distinguished from the 

 curculio, however, by lacking 

 the humps on the wing-covers. 

 It is about one-quarter inch 

 long, with a snout half as long, 

 the wing-covers are a leaden- 

 gray color, finely spotted with 

 black and brown, while the 

 thorax and head are marked 

 with ochreous yellow. 



Life History. Like the cur- 

 culio the beetles hibernate over 

 winter and appear in the spring 

 as the trees blossom. At first 

 they puncture the calyx and feed 

 on the ovary of the flower, com- 

 pletely destroying it for fruit pro- 

 duction, and then puncture the 

 growing plums, both for food 

 and for egg-laying. In feeding 



on the plums the adults gouge out small round holes, from which 

 gum exudes. Like the curculios, they have the habit of feigning 

 death and dropping to the ground when disturbed. The eggs 

 are laid while the pit of the plum is still soft. The female beetle 

 drills a small hole in the plum, which is larger below, and in it 

 deposits a small yellowish-white egg, whose outer end lies flush 

 with the surface of the plum. As soon as the larva hatches it 

 eats its way into the pit, feeding upon the meat of the seed until 



* Coccotorus scutellaris Leo. Family Curculionidoe, 



FIG. 508. The plum gouger (Cocco- 

 torus scutellaris Lee.): a, plum 

 stone showing exit hole of larva; 

 b, adult; c, side view of head of 

 beetle enlarged. (After Riley 

 and Howard, U. S. Dept. Agr.) 



