INJURIOUS TO CUCUMBER, SQUASH AND MELON 129 



migrate to the fruit when about half grown. Many of those 

 that start feeding on the chister of terminal buds burrow down 

 into the stem and complete their grow th there ; some are found 

 in the leaf petioles. The vines are often riddled in this way 

 but the greatest injury is caused by the burrows made in the 

 fruit. On reaching the fruit, some of the caterpillars feed for 

 a time in the rind wdiile others burrow directly to the center. 

 While the caterpillar is near the surface, the excrement is thrown 

 out of the opening ; later it is left in the burrows The cater- 

 pillars often leave one fruit and enter a second or third and 

 may even migrate to another vine. In the case of cantaloupes 

 and squashes, decay is almost certain to result whenever a 

 caterpillar has gnawed through the rind, thus greatly increasing 

 the loss. 



The newly hatched larva is about yV inch in length and 

 yellowish white in color. After a short time a transverse row 

 of brownish or blackish spots becomes apparent on each seg- 

 ment. These spots become more distinct with successive molts 

 and persist until the fourth, when they are lost. In the fifth 

 and last stage the caterpillar is about f inch in length, the head 

 and thoracic shield are yellowish brown and the body is whitish, 

 yellowish or greenish, depending on the nature of the food. 

 Most of the caterpillars take on a dull coppery color above soon 

 after the fourth molt. The caterpillar becomes mature in 

 twelve to sixteen days after hatching. It then spins a loose 

 silken cocoon, usually in a curled leaf, and after resting for 

 about a day transforms into a pale green pupa, ^ to nearly f 

 inch in length, wdiich after a short time changes to brownish. 

 The head of the pupa is bluntly pointed and the caudal end is 

 acute and armed with a group of short hooked spines. In the 

 summer the duration of the pupal stage is a week to ten days. 

 The time required for the complete life cycle of the insect as 

 determined in North Carolina varies from twenty-three to 

 thirty-one days. In North Carolina there are four generations 



