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APPLIED ENTOMOLOGY 



caterpillars feed for 3 or 4 weeks, becoming three or four inches long, 

 green or sometimes brown in color. In the Northern Tobacco Worm 

 each abdominal segment is marked on the side by an oblique greenish-white 

 stripe joining a similar horizontal one at its lower end, forming a series 

 of whitish Vs. On the hinder end of the body above, is a projecting 

 green horn with black sides. The larva of the Southern Tobacco Worm 

 (Fig. 307) has only the oblique bands and the horn is usually reddish. 

 In the northern part of the range of these species there is one generation 

 a year. Farther south, two seems to be the rule, while in the Gulf 

 States three or four are claimed to occur. 



Control. — Hand picking is a frequent method of control where the 

 larvae are not abundant. Spraying when the caterpillars are first seen, 

 with arsenate of lead, standard formula, has proved effective. Applied 

 as a dust it has also given good results, but this material either as a spray 

 or as a powder should not be used on tomatoes after the fruit is half 

 grown. 



The remaining families of Lepidoptera to consider are those of the 

 suborder Rhopalocera, or butterflies. Most of the insects in this section 

 are rarely of much economic importance, their larvae feeding chiefly on 

 plants not utilized in any way as food. Occasionally some species may 

 cause local injury, but only a few need special consideration from this 

 standpoint. 



Fig. 308. Fig. 309. 



Fig. 308. — Skipper Butterfly {Epargyreus tityrus Fab.), natural size. {Original.) 

 Fig. 309. — Little Copper Butterfly {Heodes hypophleas Bdv.), about natural size. 

 (Original.) 



Famihj Hesperiidae (The Skippers). — These are rather small butterflies 

 which have a curious "skipping" style of flight. They are most frequently 

 black, or yellow and black in color, often with silvery spots or streaks (Fig. 308). 

 The larvse in this family have headg much larger than the part of the body next 

 behind, making them easy to recognize. One of the larger members of this 

 group, found in the South feeds as a caterpillar on the bean, and is known as the 

 Bean Leaf-roller. 



Famihj Lycaenidae.— In this group belong the little blue butterflies spreading 

 in most cases at least, less than an inch; similar sized dark-brown butterflies; and 

 others which are of a red or coppery color (Fig. 309), with black spots. Many 



