PARASITES HIBERNATING IN BROWN-TAIL WEBS. 



279 



tion of hibernating nests in the spring of 1907 they were placed in 

 these cages and fed. As a result of his enforced absence from the 

 laboratory at a critical period these cages lacked the proper atten- 

 tion, and things went wrong with many of them. A few, however, 

 were measurably successful, and eventually about 1,000 of the 

 Apanteles were reared and colonized. Meteorus was discovered to 

 have similar hibernating habits, and Zygobothria was also reared 

 under circumstances which were sufficient to indicate its hibernating 

 habits to the satisfaction of the junior author of this bulletin, but 

 not to that of the senior. The Apanteles, in accordance with what 

 was then the policy of the laboratory with regard to parasite coloniza- 

 tion, were liberated in no less than three widely separated localities. 

 None of the colonies, so far as known, was successful. 



As anyone who was unfortu- 

 nate enough to be associated 

 with the laboratory during the 

 spring and summer of 1907 will 

 undoubtedly be willing to 

 testify, the discomfort caused by 

 handling quantities of caterpil- 

 lars and cocoons of the brown- 

 tail moth was literally dread- 

 ful. The poisonous spines upon 

 the young caterpillars are 

 neither so abundant nor so viru- 

 lent as those upon the older 

 caterpillars, but they are bad 

 enough, and the task of feeding 

 the inmates of the numerous 

 cages which contained some 

 thousands was a task of no little 

 magnitude and one involving much- physical discomfort. The instant 

 the door of one of these cages was opened, if the day was warm and its 

 occupants active, a variable, but usually a large number would crawl 

 outside, and to attempt to brush them back was but to aiTord op- 

 portunity for more to escape. Consequently thousands did escape 

 and had to be brushed up and destroyed after each day's feeding. 

 To keep the cages clear of debris was well-nigh out of the question, 

 and every time that some attempt was made to clean them out more 

 thousands of caterpillars escaped and had to be destroyed. 



When the Apanteles and the Meteorus cocoons were discovered to 

 be present in variable abundance in several of the cages trouble began 

 in earnest, because they were for the most part firmly attached to 

 the sides, or cunningly concealed in the midst of an accumulation of 

 unconsumed food, so that much time was required to find and remove 



Fig. G7 



-Apanteles lacteicolor: Adult female and co- 

 coon. Much enlarged. (Original.) 



