244 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



only an inch or two high. The eggs are laid singly, usually upon 

 the under surface of the leaves near the top of the plant, and about 

 500 are laid by each female. The egg is of a flattened convex 

 shape, bluish-green in color, and with prominent ridges converging 

 to the apex. In midsummer the eggs hatch in three or four days, 

 but in spring and autumn a much longer time is required. The 

 young larvso are a pale yellow color, but soon assume a greenish 

 tinge, and are marked with dark spots which become more dis- 

 tinct after the first moult, when they become marked like the full- 



FIG. 175. Cotton-Worm egg parasite (Pentarthron minutem): a, adult 

 female, greatly enlarged; b, ovipositor; c, female antenna; d, male 

 antenna. (From Fourth Rept. U. S. Entom. Comm.) 



grown caterpillars, being more or less striped with black. During 

 the early season the greenish caterpillars predominate, but later 

 the black stripes become heavier and the darker forms prevail. 

 The appetites of these caterpillars are only too well known to 

 the cotton-grower. At first they are content with eating only 

 the under surfaces of the leaves, occasionally piercing through. 

 Then the leaves commence to look ragged, and when they become 

 scarce the tender twigs and buds are attacked. When they are 

 excessively abundant the larvae develop cannabalistic tendencies, 

 like the boll worms, and often feed upon the weaker caterpillars. 



