August, 1944 



Ross: Caddis Flies of Illinois 



95 



38. Clasper receptacle large, nearly as 



high as long, fig. 386//. . .valanis, p. 105 

 Clasper receptacle much shallower, 

 but usually wide, fig. 386A:-A^ 39 



39. Lateral lobes of eighth sternite close 



together at base, mesal margins 

 forming a wide V, figs. 389^, 390. . . 40 

 Lateral lobes of eighth sternite farther 

 apart, their mesal margins diverg- 

 ing less, fig. 3895 41 



40. Clasper receptacle appearing, from 



dorsal view, with a swollen portion 

 basad of dorsal point, fig. 387/. . . . 



scalaris, p. 106 



Clasper receptacle appearing, from 

 dorsal view, with basal portion con- 

 fluent in outline with dorsal point, 

 fig. 387/ frisoni, p. 105 



41. Clasper receptacle appearing, from 



lateral view, with dorsal point acute 

 and near middle, its posterior 

 "tail" slender, long and slightly 

 concave dorsad, fig. 386/C, L 42 



Clasper receptacle appearing, from 

 lateral view, with dorsal point 

 rounded or near posterior margin 

 and with posterior "tail" conse- 

 quently short, fig. 386M, A'' 43 



42. Antero-Iateral lobe of ninth tergite 



long and narrow, its apex rounded, 

 its contour following its demarcation 



line, fig. 3S6K orris, p. 106 



Antero-Iateral lobe of ninth tergite 

 narrower at base, wider at apex, 

 which is produced as a somewhat 



angulate lobe, fig. 386Z, 



bidens, p. 107 



43. Clasper receptacle with dorso-mesal 



portion narrow, fig. 386A'^. ....... 



incotnmoda, p. 106 



Clasper receptacle with dorso-mesal 

 portion wide and arcuate, with a 

 pronounced posterior loop, fig. 386A/ 

 simulans, p. 104 



44. Clasper receptacle nearly globular and 



small, fig. 3875 bronta, p. 98 



BIFIDA 

 Fig. 387. — Hydropsyche, female ninth tergite. 



