THE INSECT WORLD. 



219 



Distinct from all the forms hitherto mentioned are the ' ' flea- 

 beetles, ' ' so called because of their greatly enlarged hind femora, 

 giving them the power of making sudden leaps ending in flight. 

 We have many species, and some of them are decidedly injurious 

 and troublesome to deal with. 



The grape flea-beetle is a well-known species called Haltica 

 chalybea^ from its steel-blue color, and it feeds both as adult and 

 larva on the leaves of the grape. The larvae are blackish and 

 slender, slug-like and somewhat viscid, feeding in company 

 during a great part of their growth. They are easily controlled 

 by any stomach poison, and the Bordeaux mixture, applied as a 

 fungicide, seems to be eflective in keeping them in check. 



The genera Crepidodei^a and Epitrix contain a number of 

 small species, among which the "cucumber flea-beetle," or 

 "potato-flea," Epitrix cuciwieris, easily ranks first. As a small 

 black beetle, it eats little round holes into the leaves of potato, 

 tomato, egg-plant, and a variety of other solanaceous plants, as 

 well as into those of melon, cucumber, and other cucurbitaceous 

 vines. Potatoes seem rather the favorite food, and where the 

 beetles and their little holes are numerous the leaves turn brown 

 and die, checking the growth of the plant, and hence of the 

 crop. The larvae are leaf- and stem-miners, but do little or no 

 damage. Usually Paris-green and London-purple are satisfac- 

 tory remedies, and it has been observed that the Bordeaux mix- 

 ture acts as a deterrent when liberally used, serving thus the 

 double purpose of checking insect injury and plant disease. 

 Tobacco is also a very satisfactory material used as a decoc- 

 tion, but is scarcely economical except on a small scale or in 

 gardens. 



The "sweet-potato flea," Chcstocnema conjims, is an inter- 

 esting, if troublesome, small, bronzed beetle, attacking the leaves 

 of the young plants just after they have been set out, and eating 

 little channels along the veins, finally making the net-work so 

 complete that the leaves shrivel and dry. If the vines get a fair 

 start, they outgrow the injury very rapidly, but cold, wet weather, 

 by retarding growth, sometimes enables the insects to kill them. 

 Dipping the plants before they are set out in the arsenate of lead 

 mixture, at the rate of fifteen ounces to fifty gallons of water, will 

 prove a satisfactory protection without danger of injury to the 



