NOTES ON THE PICKLE WORM AND MELON CATEHPILLAE. 



THE PICKLE WORM. 



(Margaronia nitidalis Cram.) 

 OBSERVATIONS IN 1897. 



September 1, 1897, it was noticed at Cabin John, Md., that such, cym- 

 lings as had escaped the ravages of the vine borer, Melittia satyr ini- 

 formis, and did not yet bear developed fruit, were attacked by the pickle 

 worm boring holes into them from without. One cymling contained 

 nearly a dozen holes, and one of the larvae emerged from the largest 

 hole, which appeared to be the only one that was then occupied, and 

 started to make another. Afterwards it returned through the large 

 hole, but finally perished, evidently of a bacterial disease. Another, that 

 was nearly mature, refused to emerge from the interior of the cymling 

 which it inhabited. When last observed, September 9, it was in per- 

 fect condition, but when sought for ou the 10th it had entirely disap- 

 peared, evidently dying of the same disease that had attacked the first 

 specimen mentioned. 



Holes were also noticed in muskmelons in the same garden, and 

 September 11 a larva was cut from one and kept until the 16th, feed- 

 ing on bits of cymling. On the morning of this date it left the piece 

 upon which it was feeding and in the afternoon began to spin up. On 

 the following day it completed a very fragile cocoon and remained 

 motionless, hanging downward. The cocoon was formed that night. 



An infested cantaloupe brought to the office from Ballston, Ya., Sep- 

 tember 15, and confined like the other, showed the work of this larva, 

 which cast out large quantities of frass and excremental fluid for three 

 days. On the 20th, however, it had ceased, and when the fruit was 

 cut open nothing could be found. It had evidently fallen a prey to the 

 disease which had killed the other, as there was no possibility of escape. 



A larva was taken upon a leaf of cymling on the experimental plat 

 of the Department September 30. 



October 1 and 2 the work of this species was observed on the office 

 plat of cymling squashes, in buds, in ovaries, and in immature and 

 nearly ripened fruit. Larvae were found at work in all of these parts 

 of the plants, and openings quite different from those of the vine borer, 

 were also found in the stems ; and, although the larvae were not observed, 

 it is more than probable that all of them were due to the work of the 

 caterpillar of this species, as they had plainly been made by a cater- 

 pillar boring into them from without. 



A larva taken from a cymling October 1 began to spin up its cocoon 



the day following, and transformed to a chrysalis on the 5th. On the 



25th it issued as an adult, having remained three or four days in its 



cocoon before transforming and twenty days as a chrysalis. 



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