33 



Fig. 29. — Prodmia ornitlnxjaUi: dark form, 

 male, above; pale form, female, below — 

 somewhat enlarged (original. Division of 

 Entomology). 



food, as with so many other forms of cutworms, consists of wild 

 grasses of little or no value, and when grasses or weeds are replaced 

 by crops these are apt to be attacked, under favoring conditions. 



THE COTTON CUTWORM. 



{Prodenkc ornitJiogulli Guen. ) 



This species, although called a cut- 

 worm, has little in common with pre- 

 ceding species, being more distinctl}'^ 

 marked, more or less diurnal in habit, 

 and in having the cutting trait some- 

 what feebly developed. In fact, it 

 more nearly resembles the boll worm 

 in its habit of boring into the bolln 

 of cotton and the fruit of tomato. 

 It is a ver}" common species, but as a 

 rule not especially destructive, as it 

 is more solitary than the ccmmon 

 cutworms. It has l)een observed 

 attacking and doing more or less 

 injury to beets, potato, asparagus, 

 cabbage, cucumber, peach, and eottonwood. It is also common on 

 violet, morning-glory, and other ornamental plants, and on weeds, 

 and is frequently found in greenhouses. 



The moth has a wing expanse of a little 

 less than 1^ inches, and is quite distinct 

 from any which have already been con- 

 sidered, the fore-wings having a more 

 complicated pattern. There is much varia- 

 tion in the colors, which has caused differ- 

 ently colored varieties to be described as 

 species. Two extreme forms are shown in 

 figure 29. That they are mere colorational 

 varieties of one species has l)een proved 

 by the writer by rearing both from an egg 

 mass deposited by a single female (Bui. 27, 

 new series, Div. Ent. , pp. 64-73, 11-i). 



The larva is subject to the same varia- 

 tion as the moth. The ground color is 

 generally olive or greenish brown, finely 

 lined with dark gray and brown, while the 

 upper surface is ornamented with a double 

 row of velvety black or greenish spots, which give it a striking appear- 

 ance. A pale form of the larva is shown in figure 30 at a and a darker 

 form at 5. It is a singular fact that in the writer's experiments the 

 pale larva produced the dark form of moth and the dark larva the 

 14612— No. 43— 03 3 



a b 



Fig. 30. — Prodenia ornithogalU: a, pale 

 form of larva; 6, dark form of same; 

 r, lateral view of abdominal proleg 

 segments of pale form; rf, same of 

 dark form — all enlarged (original. 

 Division of Entomology). 



