INSECTS INJURIOUS TO THE TOMATO 



231 



longer or shorter proboscis of the moth of each. The pupa; 

 measure about two inches in length. 



The Northern species occurs throughout the United States 

 and into Canada. It is also found on Jamestown weed, matri- 

 mony vine and ground cherry. The moths appear from May to 

 June, according to locality and season, and as far north as 

 New York City two generations are annually produced. The 

 writer and others have noted two generations in Maryland and 

 Virginia, while as far south as Florida, according to Quain- 

 tance, a third generation occurs. The moths deposit their 

 eggs, usually singly, on the under surface of leaves. The eggs, 

 according to Alwood's observations in Virginia, hatch in from 

 four to eight days, and the caterpillars in the course of their 

 growth cast their skins four times in less than a month. When 

 full grown they burrow into the soil and transform to pups. 

 Both "worms" are sometimes quite dark in color, but when they 

 turn nearly black they are usually infected by a bacterial dis- 

 ease, which invariably kills them (fig. 147). 



Fig. 147.— Southern tobacco worm dead and shriveled from bacterial disease. Natural 

 size. (After Howard, U. S- Dept. Agr.) 



Few observing persons have failed to see at sometime in 

 their lives the caterpillars of these or other sphinx moths en- 

 tirely covered with little white oval cocoons. These produce 

 small four-winged parasites, and it is owing to the abundance 

 of these and the bacterial disease that the insects are not 

 more numerous than they are. 



Remedies. — The amount of damage done by tomato worms 

 will vary according to the vigilance of the grower. On small 

 patches the "worms" are readily seen after a little experience. 



