THE CANADIAN ENTOMOLOGIST. 301 



with no attempt at placing tliem, were this possible. In three days all 

 the larvae had hatched from eggs deposited by females on September 13th. 



The larva, when newly emerged, is transparent and vitreous in 

 appearance. 



In the breedmg experiments considerable ditificiilties were encountered 

 owing to the prevalence of the entomophagous fungus, Isaria fariiiosa 

 (Dicks) Fr., which repeatedly attacked the sawfly larvae under observa- 

 tion. This caused the chalcid larvae to cease feeding and leave the host 

 usually one or two days before the fungus was observed. On this account 

 no observations of a continuous nature could be made upon the same 

 chalcid larvae. Nevertheless, the observations were made upon larvae 

 which emerged from eggs all deposited on the same dates, namely, 

 September 13th and 14th, on cocoons which were separated and kept 

 under observation. They belonged, therefore, to the same series of larvae, 

 and the observations will be given as if they appertained to the same 

 larvae, which, under the circumstances, is permissible. 



Sept. 18. — Two days after emerging from the eggs the larvae were all 



1910. feeding, being attached to the host larva by their heads in leech- 

 like manner. For a day or two they did not appear to leave 

 the place of original attachment. 



Se^)!:. 21. — Several larvae had moved their positions, one being attached 

 to the eye of the host larva. 



Sept. 27. — Two larvae from one of the cocoons left the cocoon and 

 travelled one or two centimetres from the cocoon. They were 

 replaced in the cocoon, but had evidently ceased feeding, 

 although another larva in the same cocoon had its head still 

 buried in the side of the host. 



Subsequent observations and examination indicated that these larvae 

 were full grown. The larv?e may become mature, therefore, in about 

 twelve days. 

 Oct. 9 — The larvae were still in the cocoons, full grown and not feeding. 



They hibernate apparently as full-grown larvae in the cocoons 



of the host. 

 Mar. 3. — Four of the hibernating larvae had pupated, but several larvae 



1 9 11. still remained unchanged. 

 Apr. 21. — Two adult chalcids emerged. 



This would make the time of development of the over-wintering 

 brood about seven months, under experimental conditions. Passing the 



