irregular transverse line from one stigmatal stripe to the other. The 

 breathing- pores are black in color, the head brownish, and the entire 

 ventral portion light. 



The pupa. — When full grown the bollworm leaves its food plant, 

 burrows below the soil surface some 2 to 5 inches, and constructs a 

 more or less upright cell, reaching to near the surface of the ground 

 to allow of the ready exit of the moth. At the bottom, the tube is 

 somewhat more enlarged, and here the larva sheds its skin and enters 

 the quiescent pupal stage. There is considerable variation in the 

 method of pupation, depending on the character of the soil, and not 

 infrequently this stage may be entered within the ear of corn or the cot- 

 ton boll in which the larva was feeding. The pupal stage during sum- 

 mer lasts from nine to twelve days. 



The adult. — The parent moth, like the larva, is extremely variable 

 in general color, ranging in diiferent 

 individuals from a dull ochre-yellow 

 to a. dull olive-green. The wing ex- 

 panse is about li inches, and the 

 body is about seven-eighths of an 

 inch in length. The males ma}' be 

 most readily distinguished from the 

 females by the stouter abdomen of 

 the latter. The accompanying illus- 

 tration (fig. 2) shows the bollworm 

 moth in a rather characteristic posi- 

 tion, and will aid in its identifica- 

 tion, where help is needed. 



Life cycle. — From the above state- 

 ments as to the length of the re- 

 spective stages, it is seen that the 

 insect may go through all of its 

 transformations from egg to adult, during summer, in about twenty- 

 three to thirty days. The average of six individuals reared during 

 June and July, at Victoria, Tex., was twenty-eight days. During 

 spring and fall the rate of development is much slower. The average 

 time for the complete life cycle of nine individuals during the spring 

 at Victoria was forty-four days. 



Fig. 2. — Bollworm moth in natural position, 

 wings folded; about twice natural size (orig- 

 inal). 



FOOD PLANTS. 



The bollworm is practically omnivorous, and the list of plants upon 

 which it has been found feeding is very large. In the United States 

 it is destructive principally to corn, cotton, tomatoes, and various gar- 

 den crops. The combined annual loss from this species in this and 

 foreign countries must be very great, and easily places the bollworm 

 among the foremost injurious insects of the world. 



191 



