FLEA-BEETLES 333 



portant insect enemy of that crop. It has been observed feed- 

 ing on sugar-beet, corn, wheat, oats, timothy, bhie-grass, buck- 

 wheat, red clover, raspberry and box elder. 



The beetle is about te inch in length, pitchy black with a faint 

 bronzy reflection. The antennae and legs, except the hind 

 femora, are reddish yellow (Fig. 211). The winter is passed 

 by the beetles in rubbish, especially along hedgerows and 

 woodlots. In New Jersey they appear on the sweet potato 

 plants as soon as transplanted in May. They do not eat holes 

 through the leaves but eat out grooves or channels in the 

 upper surface, usually beginning along 

 the more prominent veins. Later a large 

 part of the surface may be eaten off; the 

 leaf wilts, turns brown and dies. Young 

 plants are often killed in this way or so 

 badly stunted that they do not produce a 

 good crop. In New Jersey the beetles 

 are most abundant in May and the first 

 part of June, when they begin to leave Fig. 211. 

 sweet potato, and by the first of July 1""^%^ flea-beetle 

 very few are left. On leaving the sweet 

 potato, Ihey migrate to bindweed, which is often found grow- 

 ing as a weed in the fields or along the fences. It is on this 

 plant that the larvae have been found feeding on the fine 

 roots but not tunneling the larger roots. When full-grown, 

 the larva is about \ inch in length, white, with a brown- 

 ish head. The whitish pupa? are found in earthen cells in the 

 ground. The beetles of the new brood begin to appear in late 

 July but do not return to the sweet potato in large numbers until 

 the following spring. There is only one generation annually. 



Conirol. 



Fortunately this flea-beetle does not attack sweet potato 

 plants in the seed-bed to any appreciable extent. ^Nlost of the 



