336 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



Gulf, and is one of the most common pests of beets and spinach, 

 while its native food plants are chickweed and lambsquartcrs. 



Life History. The beetles hibernate over winter and emerge 

 in the spring during April and May. The buff or orange eggs are 

 laid on end in small masses, "at the bases of the plants infe ted, 

 on bits of leaf or earth, or even within the earth " according to 

 Forbes. The eggs hatch from sometime in April to early July, 

 according to locality. The larva? usually feed on the under side 



FIG. 241. The sp'nach flea-beetle (Disonycha xanthomelcena Dalm.): a, 

 beetle; b, egg mass; bb, sculpture of egg; c, larva; d, pupa; e, voung larva; 

 /, abdominal segment of same a, c, d, five times natural size; b, more 

 enlarged; bb, f, highly magnified. (After Chittenden, U. S. Dept. Agr.) 



of the leaf, keeping together in families which migrate from leaf 

 to leaf while young, and drop to the ground as do the beetles- 

 when disturbed. While young they merely gnaw the under 

 surface of the leaf, but later they eat through and riddle it with 

 round holes, in which they are aided by the beetles. The full- 

 grown larva is about one-quarter inch long, of a dull gray 

 color, except on red and purple beets, on which it assumes the 

 color of the plant attacked, is of a cylindrical form, and the seg- 

 ments are strongly marked by rows of raised tubercles, each of 

 which bears a black hair at the tip. The larvae become grown 



