304 N. E. McINDOO 



end of group 2. In groups 1 and 2 there are 281 and 50 pores 

 respectively; in the former group (fig. 4) the pores are close to- 

 gether while in the latter (fig. 5) they are more scattered. The 

 pores vary considerably in size; in group 1 most of them are 

 small, with the diameter of the largest three times that of the 

 smallest, while in group 2 almost all of them are comparatively 

 large, with the diameter of the smallest one-half that of the largest. 

 In group 1 scarcely any rows are discernible, but in group 2 the 

 rows are more sharply defined. The openings (PorAp) in the 

 pores are usually round, although several are oblong, and the 

 long diameter of the oblong pores is more or less parallel with 

 that of the group. 



Group 3 is found on the upper surface of the front wing (fig. 

 2) and occupies nearly the entire surface of the median plate 

 (fig. 6, Md), leaving only a narrow margin on all sides. This 

 group is long and slender, with its tapering end pointing toward 

 the proximal and posterior margin of the subcosta (Sc). Its 

 pores are considerably scattered, although they lie in more or 

 less definite rows (fig. 7). The pores are about equal in diameter 

 and the diameter of the largest is never more than twice that of 

 the smallest. In this group there are 174 pores, nearly all of 

 which have round apertures. 



Group 4 is present on the lower surface of the hind wing (fig. 

 1) and covers most of the anterior half of the union of the radius 

 and media (fig. S, R -\- M). Its distal end is the more pointed 

 and its pores are arranged in irregular rows (fig. 9) . There are 

 83 pores of about equal size. 



Group 5 lies on the upper surface of the hind wing (fig. 2) 

 and occupies nearly all of the surface where the radius and media 

 unite (fig. 10, R + M) and extends sHghtly over the subcosta 

 (Sc). The proximal and narrower end of the group points di- 

 rectly toward the proximal end of the subcosta. There are 209 

 pores, which can scarcely be said to lie in rows (fig. 11). Most 

 of the pores are small, with the diameter of the largest three 

 times that of the smallest. 



Group 6 is a double group having the shape of a figure 8, 

 located at the proximal end of the femur (fig. 1) on the outer 



