154 HYMENOPTERA. 



21. P. coloradensis . Genital armature. 



22. P. nevadensis. Genital armature. 



23. P. asininus. Genital armature. 



24. P. wootoni. Genital armature. 



Plate III. 



25. P. modestus. Eighth ventral plate. 



26. P. zizics. Eighth ventral plate. 



27. P. episcopalis . Eighth ventral plate. 



28. P. fossata. Eighth ventral plate. 



29. P. zizice. Seventh ventral plate. 



30. P. zizice var. dunningi. Seventh ventral plate. 



31. P. potens. Seventh ventral plate. 



32. P. basalis. Genital armature. 



33. P. potens. Eighth ventral plate. 



34. P. basalis. Eighth ventral plate. 



35. P. potens. Genital armature. 



36. P. basalis. Seventh ventral plate. 



Plate IV, 



37. P. rudbeckicB . Seventh ventral plate. 



38. P. cressoni. Seventh ventral plate. 



39. P, cressoni. form satticulcs. Seventh ventral plate. 



40. P. rudbeckice var. bakeri. Seventh ventral plate. 



41. P. varifrons. Seventh ventral plate. 



42. P. grossicornis . Seventh ventral plate. 



43. P. tridentulus. Seventh ventral plate. 



44. P. conspicua. Seventh ventral plate. 



45. P. varifrons. Eighth ventral plate. 



46. P. tridentulus. Eighth ventral plate. 



47. P. tridentulus. Eighth ventral plate (lateral view). 



48. P. grossicornis . Eighth ventral plate. 



49. P. conspicua. Eighth ventral plate. 



50. P. rudbeckice. Eighth ventral plate. 



51. P. cressoni form saniculcB. Eighth ventral plate. 



52. P. cressoni. Eighth ventral plate. 



53. P. cressoni. Eighth ventral plate. 



54. P. rudbeckice var. granulatus. Eighth ventral plate. 



Plate V. 



55. P. asininus. Seventh ventral plate. 



56. P. wootoni. Seventh ventral plate. 



57. P.polifolii. Seventh ventral plate. 



58. P. coloradensis. Seventh ventral plate. 



59. P. calvus. Seventh ventral plate. 



60. P. cookii. Seventh ventral plate. 



