THE CANADIAN ENTOMOLOGIST 263 



ovarial chamber, and the developing seeds appeared to be in normal 

 condition. • 



Description of Third-stage Maggot. — Length, extended, 9 to 

 10 mm. Pale yellowish or straw-colored, anal plates and cephalo- 

 pharyngeal skeleton black. Mandibular hook double, not coal- 

 esced. Anal plate in one transverse piece of chitin, with a sharp 

 spine pointed upward from each end. Anal stigmata situated one 

 on each side in end of anal plate next to and just inside of the spine. 

 At outer end of anal plate on each side is a chitinous black ocellus. 

 Ventral surface of body has spinose areas at junction of segments, 

 being eleven half rings of microscopic spines, the front one faint and 

 situated opposite the pharyngeal sclerites, the hind one on the sub- 

 anal proleg-like hump or tubercle. Dorsum of body without spines 

 or spine areas. Thirteen segments appear marked by integu- 

 mental divisions, and counting the apparent second segment as II. 

 and III. the total is fourteen, XIII carrying the subanal tubercle 

 and XIV. the anal plate, though the last is small and ill-defined. 



The maggot jumps by curling the body until the head and anal 

 plate meet, the mandibular hook being appressed ventrally to the 

 dorsal surface of the anal plate, whose lateral hooks are dorsally 

 directed, the anal plate being then forcibly thrust free from the 

 mandibular hook by a sudden and rigid straightening of the body 

 from the anal end, while the mandibular hook is maintained con- 

 tinuously at resistant tension. This produces the leap, probably 

 after the same manner as in the maggot of Piophila. While the 

 body is curled, the ventral surface represents the concavity and the 

 dorsal the convexity of the curve assumed. Probably this jumping 

 power of the maggot has been developed for the purpose of escaping 

 the ants or other enemies when the flower is abandoned for pupa- 

 tion in the soil. 



On January 26 the maggots were found to have issued from 

 the bloom. Soil was supplied to three of them, into which two of 

 them immediately entered, but the third had already begun to 

 contract for pupation and remained on the surface. Issuance had 

 not taken place up to some fifteen or twenty days after, but on 

 February 27 the three files were found issued, perfectly trans- 

 formed, and dead. The pupational period is evidently close to 



