418 CALIFORNIA ACADEMY OF SCIENCES. [Proc. 3D Ser. 



EXPLANATION OF PLATE XXV. 



All the figures were drawn with the aid of a camera lucida, with the 

 optical combinations oc. 2, obj. 3, Leitz, or oc. 4, obj. AA, Zeiss. 



Fig. 1. Vulvar lamina of Herpetogomphus viperinus Selys, female. 



Fig. 2. Vulvar lamina of Herpetogomphus claps Selys, female. 



Fig. 3. Apex of the abdomen of Lestes tenuatus Rambur, male. The right 

 superior appendage is represented as broken off near the base 

 to show the right inferior appendage (inf. app.) below it; inf. app. 

 is homologous to the part marked app. lat. in fig. 5; app. a 1 ., 

 appendix dorsalis of Heymons, or tergum of the eleventh seg- 

 ment, which is homologous with the inferior appendage in figs. 

 5, 7 and 13. 



Fig. 4. Left side of the apex of the abdomen of Argia pulla Selys, male. 



Fig. 5. The same of Herpetogomphus viperinus Selys, male; see the 

 explanation of figure 3. App. lat., appendix lateralis (sternite 

 of eleventh segment) of Heymons. 



Fig. 6. Left side of apex of abdomen of Argia Harknessi, sp. nov., male. 



Fig. 7. Right side of apex of abdomen of Macrolhemis inacuta Calvert, 

 male. 



Fig. 8. Left side of apex of abdomen of Argia exlranea Hagen, male. 



Fig. 9. Left side of the genitalia of the second abdominal segment of 

 Anatya normalis, sp. nov., male, the insect being held upside 

 down, as also in figs. 10 and 12. 



Fig. 10. The same of Macrothemis inacuta Calvert, male. 



Fig. 11. Left side of apex of abdomen of Argia fissa Sely - s, male. 



Fig. 12. Left side of the genitalia of the second abdominal segment of 

 Brechmorhoga postlobata Calvert, male. 



Fig. 13. Right side of apex of abdomen of Anatya normalis sp. nov., male. 



Significance of Reference Letters. 



In figs. 9, 10 and 12 — 



at. anterior lamina. 



gl. genital lobe. 



h. hamule. 



ih. internal branch of hamule. 



p. penis. 



sh. external branch of hamule. 



/. posterior tubercle of genital lobe. 



vp. vesicle of the penis. 



