578 KEW JERSEY AGRICULTUEAL COLLEGE 



there were 141 cocoons, and September 16th there were yet all stages 

 down to small larva3 in silk-closed berries. 



The full-grown larvae are rather more than half an inch in length, 

 of a bright green color, with a variably-marked, reddish tinge on the 

 back. The head is a little narrower than the first body segment and 

 is yellowish, except for the brown mouth parts. The body segments 

 are transversely wrinkled and clothed with a few sparse, rather long 

 hairs. 



These caterpillars winter in silken cocoons, which they make by 

 first rolling in the saiid, gluing the surrounding particles together with 

 saliva, and then spinning their web inside the rough casing thus 

 formed. The moist sand of the surface of a cranberry bog is just such 

 a surrounding as the insect needs. If the bog remains unflooded 

 during the winter the great majority of all the larvfe will survive to 

 complete their transformations. If the bog is covered with water a 

 considerable percentage will be killed off, this percentage increasing 

 in proportion to the earliness of the flooding. 



Mr. Thayer's notes show that of the cocoons collected and sub- 

 merged soon after they were formed, practically none survived, and 

 that late submergence and early withdrawal in all cases favored the 

 insects. 



Pupation does not take place within the cocooii until shortly before 

 the m.oths are due to emerge. May 33d is the first date at which 

 pupa? were actually noted in confinement, and June 17th is the earliest 

 for actual bog conditions. As to the latest change, that did not occur 

 until August, when some of the new larvae were already almost full 

 grown. There is no actual record of a lap-over, but by the time the 

 last moth is on the wing the first-l)orn caterpillars are already full 

 grown, if not actually in cocoon. 



Remedial Measures. 



These have been indicated in the discussion of the life cycle and 

 in the references to Mr. Thayer's results. Flow as soon after picking 

 as is eoiivenient and safe, and keep on tlie water, either altogether or 

 for two or three weeks, if improvement or other work is necessary on 

 the bogs. But in no case flow permanently before the middle of Octo- 

 ber unless the foliage has ripened and turned. This process is advan- 

 tageous also as against the girdle-worm where that occurs, so that a 



