HENRY J. FRANKLIN. 259 



Second segment covered with ferruginous-red pile. 



melanopygiis. 



46. Black interalar band more or less distinct 47. 



No trace of black interalar band perplexus. 



47. Posterior border of hind metatarsi fringed with long, loose hairs. 



polaris. 



Posterior border of hind metatarsi fringed with short hairs or 



bristles pennsylvanicus. 



48. All the dorsal abdominal segments after the first two entirely 



covered with black pile 49. 



Not all the posterior dorsal abdominal segments entirely covered 

 with black pile 50. 



49. Distinct black interalar band present; western pleuralis. 



No distinct black interalar band; eastern vagans. 



50. Black interalar band more or less distinct ; yellow spot of pile on 



face, when present, not nearly reaching the margin of the 



eye on either side 58. 



Black interalar band not at all distinct, the middle of the dorsum 

 of the thorax having only a clouded appearance due to the 

 thorough mixture of yellow and black hairs ; yellow pile on 

 face very nearly reaching the inner margin of the eye on 

 each side 60. 



51. Black interalar band extended behind into a distinct V on the 



middle of the scutellum 61. 



Posterior border of interalar band straight or nearly so 63. 



52. First dorsal abdominal segment covered for the most part with 



black pile occidentalis. 



First dorsal segment entirely covered with yellow pile 53. 



53. Some of the dorsal abdominal segments covered with ferruginous- 



red pile melanopygus. 



None of these segments covered with ferruginous pile..impatiens. 



54. Some of the apical dorsal abdominal segments covered with yel- 



low pile 55. 



None of the apical dorsal abdominal segments covered with yel- 

 low pile biniaculatus. 



55. Scutellum and basal abdominal segment above yellow. ..fernaldi. 

 Scutellum and basal abdominal segment above black. 



californicus. 



56. Face with a strong touch of yellow pile about and below the bases 



of the antennas 57. 



Face with very little or no light pile a£S.nis. 



57. Third dorsal abdominal segment black vagans. 



Third dorsal segment yellow perplexus. 



58. Third dorsal abdominal segment with little or no yellow pile ; 



colors (ferruginous, yellow and black) usually strong and 

 sharply defined ; body rather slender frig'idus. 



TRANS. AM. ENT. SOC, XXXVIII. 



