Braconidae 489 



through the winter without success. After hatching from the eggs the 

 larvae spin hibernacula in sheltered locations in which they pass the 

 winter. Apparently the winter mortality is very high even under nat- 

 ural conditions. Under the abnormal experimental conditions devised 

 total losses occurred, until it was found that a favorite location for 

 hibernating is under the thin bark scales on branches of jack pine, and 

 that if branches on which the insects were hibernating were kept out of 

 doors, in a place where the sun did not strike them, a considerable 

 number of larvae survived. 



Feeding Period. In the spring, when the larvae emerge from hiberna- 

 tion, they must be provided with a supply of expanding buds and 

 young foliage. It was found that the easiest way to supply satisfactory 

 food for them was to confine them on the tree in muslin bags similar to 

 those described for the jack pine sawfly. The less the larvae are handled 

 the lower the losses. Therefore it was found desirable to place only a 

 few larvae in each bag so that enough food would be available for their 

 complete development without transferring them to new branches. 

 About five larvae to the branch end proved satisfactory. 



Pupation and Emergence. Pupation occurs on the branches where 

 the larvae feed. Therefore it was found that the most satisfactory way 

 of handling this stage was to leave pupae in position within the bags 

 until the moths emerged. At this stage, it was necessary to watch their 

 development carefully so that the moths might be removed as soon as 

 possible after emergence. 



Reference 



For the rearing of sawflies see p. 517. 



Family 



BRACONIDAE 



TECHNIQUE OF CULTURING HABROBRACON 



JUGLANDIS 



P. W. Whiting, University of Pennsylvania 



THE first requisite is a large number of well developed caterpillars 

 of the mediterranean flour moth, Ephestia kuehniella [see p. 355]. 

 It will take at least 5 weeks to obtain these if a good supply of moths is 

 available immediately. If only a small culture of Ephestia is available, 

 7 or 8 weeks should be allowed for obtaining a good supply of moths. 

 Six to ten wasps may be obtained from one caterpillar. Fifty to 300 

 caterpillars may be obtained from one pair of moths. 



Equipment Needed. Shell vials (70 x 20 mm.) plugged with cotton 

 wrapped in fine meshed cheesecloth. The plugs may be conveniently 



