246 



Illinois Natural History Survey Bulletin 



Vol. 23, Art. 1 



5. Arms of tenth tergite wide, short and 



divergent, fig. 841 injusta, p. 252 



Arms of tenth tergite narrow, long, 

 parallel and curved to left at tip, 

 fig. 842 ignita, p. 252 



6. Dorsal apex of tenth tergite vestigial, 



fig. 843 aba, p. 249 



Dorsal apex of tenth tergite long, fig. 

 844 7 



7. Clasper with no postero-lateral or 



mesal projection, fig. 844. . perna, p. 250 

 Clasper with postero-lateral and mesal 

 projections, fig. 845 8 



8. Aedeagus scarcely exserted, with an 



ovate body and short beak, fig. 845 

 phalacris, p. 250 



Aedeagus exserted to beyond base of 

 claspers, forming a long, curved 

 structure, fig. 846 9 



9. Tenth tergite gradually tapering from 



near base to apex, fig. 846 



flavescens, p. 251 



Tenth tergite clavate, fig. 847 10 



10. Lateral lobe of clasper only slightly 



longer than mesal lobe, fig. 847. . . . 



Lateral lobe of clasper at least nearly 



twice as long as mesal lobe, figs. 849, 



850 



11. Cerci as long as tenth tergite, fig. 847. 



baris, p. 252 



Cerci about half as long as tenth ter- 

 gite, fig. 848 dipsia, p. 252 



11 



12 



845C 



PHALACRIS 



PERNA 



845A 



Figs. 839-845. — Triaenodes, male genitaha. A, lateral aspect; B, tenth tergite; C, claspers, 

 ventral aspect. 



