OF WASHINGTON. VOLUME XIV. 1912. 209 



a dozen eggs are laid in one puncture. The insect appears 

 to sit facing up the stem and when but two or three eggs are 

 laid in one puncture the ovipositor is directed only down the 

 stem, but when several eggs are deposited some are directed 

 towards the base of the stem and some towards the tip, 

 showing that the ovipositor is directed towards the base of 

 the stem part of the time and then towards the tip. I do not 

 know whether the insect withdraws the ovipositor in changing 

 the direction of the puncture. 



The eggs are usually placed in the wood; very close under 

 the bark in the larger stems, as shown by the specimens ex- 

 hibited, but in the smaller stems they are sometimes deposited 

 in the soft inner pith. Green stems seem preferable for pur- 

 poses of oviposition, but fresh eggs are also found in dead stems. 

 -Upon request from the chair Professor Parker spoke of his 

 experience with Cuterebra in rabbits; he had shot a half- 

 grown rabbit in August in Knox County, Ohio, which had 

 three infestations, one larva already dropped out, another 

 dropped out when he lifted the rabbit up from the ground, and 

 one larva had to be pressed out. In 1907 he had likewise seen 

 full-grown larvae in a rabbit not -more than 2 or 3 months 

 old, which would prove a rapid larval growth of this species, 

 the adult of which appeared in June. 



Mr. Knab mentioned that the mature larva are frequently 

 received from hunters in the fall. This spring he succeeded 

 in breeding an adult from a larva received last fall. May and 

 June is the normal time of appearance of the fly. 



Mr. Walton said he had bred Cuterebra cuniculi in Harris- 

 burg, Pa., the fly appearing in June. 



Mr. Caudell asked whether the larvae occurring in rats were 

 of the same species. Mr. Knab answered that he has not 

 seen larvae of this species and that he was not aware that it 

 had been bred, but as Cuterebra seems to be restricted to 

 rodents it is probable that the larvae in rats are also Cuterebra. 

 Probably different species of Cuterebra infest different ro- 

 dents indifferently. One species, C. emasculator, has been 

 described from the genitalia of a male squirrel ; but he did not 

 think that species was peculiar to the squirrel. Mr. Walton 



