Entomology of the Illinois Hiver, 253 



Odontomyia. 



Two species of this genus {cincta and vertehrata) were 

 studied at Havana, quite unlike in structure and 

 easy to distinguish. No other images of this genus were 

 found on shore during the season's work. 



The females were seen ovipositing in largo numbers on 

 stakes projecting above the water, always upon the 

 overhanging side, which was thickly covered wit"h over- 

 lapping clusters. Dead branches in the water, reeds, and 

 stems of various plants, also served the same purpose. 

 The method of oviposition seemed to be the same in both 

 species. The females all stood head downward except one. 

 The long and narrow eggs were placed parallel to the 

 longitudinal axis of the mass in an irregular oval or 

 mytiloid low-convex mass, to the number of several 

 hundred, closely laid, their tapering ends inserted be- 

 tween the ends of those adjacent to them. The fly 

 having selected with its ovipositor a suitable place for 

 an Qg^, and having placed its tip where the end of 

 this egg is to be inserted or attached, the ovipositor 

 is suddenly withdrawn, leaving about two thirds of the 

 length of the egg protruded in its place. Then, after 

 a momentary pause, the ovipositor is more slowly 

 withdrawn from the remaining portion of the e^^. The 

 flies were quite imperturbable during the operation. 



As mentioned under Stratiomyia norma the nymphs 

 of that species and of Odontomyia are parasitized by 

 large chalcids of the genus Smicra. In a cage containing 

 larvae and pupae of cincta and a single pupa of Strati^- 

 myia norma; some of these chalcids emerged July 6, all 

 escaping but one, which was dpfermined by Mr. W. H. Ash- 

 mead as Smicra rufofemorata. The small rounded holes 

 made in the larval skin by the escaping chalcids wore 

 present in the Stratiomyia pupa and several of the cincta. 

 A well-formed example of a closely related species, S. 

 microgaster. was extracted from a pupa of 0. vertefrrata^ 

 also on July 6. The latter chalcid was again found July 



