27B 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 antenna; 



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. How-ever, 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 rostratiim, 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- extended eastward until 1874, when it reached the 

 ratio potato - beetle, . ,^ t^. ,1 • , ■ , . , r 1 1 . 



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



(Twice natural size.) Jn 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, Galerncella luteola (Fig. 384), a common European pest. 

 It first got to this country in 1834 and is how "in all jirobability responsible 

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



