Occasional Papers of the Museum of Zoology 7 



rowed, the apical tooth is more or less distinctly larger, and 

 there is a pretty uniform decrease in size basally. The num- 

 ber and spacing- of the teeth vary in the ditferent species of 

 this group but are variable and of little use apparently in 

 recognizing species. The single-rowed or paved condition is 

 however recognizable at a glance. It is a most useful char- 

 acter, permitting for the lirst time the certain determination 

 of the group relationships of any female specimen. The 

 ovipositor consists of four parts, two anterior and two poster- 

 ior, each anterior closely appressed to its corresponding poster- 

 ior process. Each anterior process has its distal outer edge 

 headed or convoluted in a manner apparently characteristic of 

 eacb species. The posterior process has along its distal outer 

 border a series of oblique grooves or teeth, which extend basally 

 farther than the beading or convolutions of the anterior pro- 

 cess. When viewed from the ventral surface only the two an- 

 terior processes are seen, except that in certain cases the edge 

 or apex of the posterior processes mav be in view. This 

 latter condition is especially true in the case of those species 

 with narrow anterior processes. In those species with wide, 

 flattened anterior processes, the apical portions of the 

 posterior processes, bearing the grooves or- teeth, lie well 

 within the outer edges of the anterior processes and are 

 not visible in a ventral view. The ovipositor is narrow in 

 group 3, and widest in Oxystigma. 1 have studied it in 

 only a limited numljer of species as it is usually concealed 

 by the valves, and I did not wish to relax older and typical 

 material loaned me for study. A thorough study of this 

 organ must await the accumulation of more material. Tlic 

 apical beading of the anterior process I think has little or 

 no function in the insertion of the ovipositor. In fact, 

 it seems these irregularities would render the insertion more 



