278 Beetles 



the familiar Colorado potato-beetle being one of the largest species in the 

 family; the body is short, more or less oval in outline, strongly convex above; 

 the head small, much narrower than the prothorax, and with the antennae 

 inserted widely apart. The adults walk slowly about on the plants on which 

 they feed, and when disturbed usually fold up the legs and fall, inert, to the 

 ground. However, they sometimes take readily to wing. The eggs are 

 usually laid in little groups on the food-plants, and the larvae, rather broad, 

 thick, and roughened, crawl about, exposed, on the leaves which they eat. 

 Sometimes they eat only the soft tissue of the leaf, skeletonizing it; some mine 

 inside the leaf, and a few burrow into stems. Most, however, eat ragged 

 holes in the leaves, and, if feeding on cultivated plants, do great injury. 

 Indeed there are perhaps more beetle enemies of our crops, shade-trees, and 

 ornamental plants in this family than in any other in the order. 



The Colorado potato-beetle, Doryphora lo-lineata (Fig. 383), with 

 robust, oval, cream-colored body, and elytra with five longitudinal black 

 stripes on each, is a notorious Chrysomelid whose gradual extension or 

 migration eastward from its native home in Colorado 

 created much excitement forty years ago. Its native 

 food-plant is the sand-bur, Solanum rostralum, a 

 congener of the potato, but after 1850 it began to find 

 its way to the potato-plants of the early settlers; by 

 1859 it had reached Nebraska, 1861 Iowa, in 1864 

 and 1865 it crossed the Mississippi and gradually 



FIG. 383. The Colo- ex t e nded eastward until 1874, when it reached the 

 rado potato - beetle, , . _..,... . . . .. . , , 



Doryphora lo-lineata. Atlantic Ocean. Finally it obtained a partial foothold 



(Twice natural size.) j n Europe, creating great consternation there, but it has 

 never got to be a serious pest across the ocean. The orange-red eggs are 

 laid on the leaves, and the larvae are curious humpbacked soft-bodied crea- 

 tures with black head and Venetian-red body. They crawl down and bur- 

 row into the ground to pupate. There are three generations a year in the 

 latitude of St. Louis, the beetles of the last brood crawling underground 

 to hibernate. 



The common asparagus-beetle, Crioceris asparagi, red, yellow, and black, 

 gnaws holes in young asparagus-heads, and the brown slug-like larvae which 

 hatch from oval blackish eggs laid on the heads also eat them. The three- 

 lined Lema, Lema trilineata, of similar shape, but yellow with three longi- 

 tudinal black stripes on each elytron, is common on "ground -cherries." 

 Their larvae have the curious habit of covering their backs with their own 

 excrement. Elm-trees in the East are often badly infested with the imported 

 elm -leaf beetle, Galerucella luteola (Fig. 384), a common European pest. 

 It first got to this country in 1834 and is now "in all probability responsible 

 for more ruined elm-trees in the Hudson River valley than all other destruc- 



