Goddard.] 212 [Oct. 2,. 



Lihellula pulcJiella. 



Fig. 13. FrameAvork, triangle, hamnles, and sternum. 

 Fig. 14. Genital bladder and side view of penis. 



Libellula quadrupla. 



Fig. 15. Genital bladder and penis — side view. 



PlatJiemis trimaculata. 



Fig. 16. Framework, triangle, liamules, and sternum 

 Fig. 17. Genital bladder and penis — ventral view 

 Fig. 18. Penis — dorsal view. 



In the above diagrams, the letters stand for organs as follows : 



a. Genital lobe. &. First segment of tergum. c. Second segment of 

 tergum. d. Third segment of tergum. e. Sternum. /. Triangular 

 appendage of sternum, g. Hamule. h. Spur of hamule. i. Truncate 

 lobe of hamule. k. Framework, m. Lateral rod of framework, n. Tri- 

 angle. 0. Left cephalic triangle of genital bladder, p^, p^, p^. Seg- 

 ments of penis, r. Right cephalic triangle of genital bladder, s. Dorsal 

 triangle in genital bladder of Celitliemis elisa. t and p. appendages of 

 l)ems of PlatJiemis ti'imaculata. « and «. Appendages of penis of Libel- 

 lula exusta. w. Caudal triangle of genital bladder, x. Membranous 

 appendage of framework in Libellula exusta. 1. Shield of third seg- 

 ment of penis. 3. Ring. 3. Hood. 4. Banner. 5. Fork. 6. Twist. 



