232 R. E. SNODGRASS. 



PLATE IX. 

 Fig. 13. Epiphragma forcipennis, distal half of abdomen, lateral view, x 20. 

 " 14. Limnophila cubitalis, terminal half of abdomen, lateral view. 

 " 15. Epiphragma forcipennis, second gonapophyses of left side and its ape 



deme (ap.) lateral view. 

 " 16. Limnobia sciophila, terminal part of abdomen, lateral view, x 221. 

 " 17. Limnophila rufibasis, guard of penis, left side, showing position of penis 



\p.) within. 

 " 18. Limnophila quadrata, terminal part of abdomen, dorsal view, x 25. 

 '" 19. Limnobia sciophila, apical appendage of hypopygium. 

 " 20. " guard of penis (p. g.) and second gonapophyses (gon. 



2), ventral view. 

 " 21. Limnophila rufibasis, base of penis, dorsal view. 



" 22. " left apical appendage of hypopygium, lateral view. 



" 23. '' terminal part of abdomen, dorsal view, x 18. 



'' 24. Amalopis constans, sternum, ventral view. 

 " 25. Limnophila rufibasis, second gonapophyses of left side. 

 " 26. Amalopis constans, dorsal view of hypopygium with appendages removed. 

 " 27. " ampla, left apical appendage of hypopygium, lateral view. 



" 28. " sternum of hypopygium, ventral view. 



'' 29. " " tergum of hypopygium, dorsal view. 



" 30. " terminal part of abdomen, lateral view, x 15. 



" 31. " constans, left apical appendage of hypopygium, inner view. 



" 32. " " terminal part of abdomen, lateral view, x 15. 



PLATE X. 

 Fig. 33. Limnobia sciophila, terminal part of abdomen, dorsal view, x 25. 



" 34. Limnophila quadrata, guard of penis (p. g.) and second gonapophyses of 

 left side (gon. 2) with its apodeme (ap.), left view. 



'' 35. Bittacomorpha clavipes, hypopygium, left side ; m, intersegmental mem- 

 brane between eighth segment and hypopygium. 



" 36. Bittacomorpha clavipes, guard of penis with penis projecting, dorsal view. 



" 37. " tergum of hypopygium, dorsal view. 



' 38. " sternum of hypopygium, ventral view. 



" 39. " left pleurum of hypopygium with base of apical 



appendage attached (ap. ap.) and dorsal transverse process. 



" 40. Ptychoptera lenis, terminal part of abdomen, lateral view. 



" 41. " tergum of hypopygium, dorsal view. 



" 42. " " penis, dorsal view. 



" 43. Ctenophora angustipennis, left lower apical appendage of hypopygium, 

 external view. 



" 44. Ptychoptera lenis, left sternal lobe of hypopygium, lateral view. 



" 45. " left apical appendage of hypopygium, lateral view. 



" 46. Ctenophora angustipennis, left middle apical appendage of hypopygium, 

 lateral view. 



'' 47. Ctenophora angustipennis, hypopygium, dorsal view. 



" 48. guard of penis, left view. 



" 49. terminal part of abdomen, lateral view, x 10. 



