140 AVILLIAM J. FOX. 



ton. C. cublcepx, I unite with moidanux as it differs only in the 

 color of the scaf)e, a trivial character and in this s])ecies a variable 

 one. ('. cfiddtHx is without douht the male of iiio/ifiiini-^. I have 

 examined over eighty specimens of this species mostly from the 

 West which indicates a common occurrence. 



6. C'rabro atriceps Cress. 



Crabro atriceps Cressou, 1. c, p. 483, 9 ■ 



9. — Space between the eyes at base of clypeus fully equal to the leuffth of 

 joints 1 and 2 of the flagellum ; pronotum not inarffined, the lateral tooth small 

 and blunt, transverse furrow indistinct; dorsuluni anteriorly with very close 

 puucture.s, indistinctly interspersed with stria', posteriorly the punctures less 

 close; mesoi)leurte rather coarsely and closely striated ; middle segment with the 

 ridge separating the upper surface from the posterior face indistinct, medial fur- 

 row broad, distinctly widened at the middle, posterior face tinely roughened or 

 rugose, without transverse striae a])ically and not ridged laterally, sides deli- 

 cately striated ; abdomen finely punctured, but more distinctly than in monlnnm. 

 Black, including the mandibles and scape ; two spots on pronotum, tubercles, line 

 on metanotuni, sometimes broken, or absent, spot at the apex of the four anterior 

 femora, sometimes wanting, a line on the outer side of tibise, and an elongated 

 spot on each side of dorsal abdominal segments 2 5, those on segment i> always 

 united, yellow ; no spots on the first segment ; the tarsi black ; wings subhyaline 

 throughout, Length 7-9 mm. 



'^ . — Head with tolerably fine and close i)unctures, the liind margin not strongly 

 margined ; space between the hind ocelli scarctily less than that between them 

 and the nearest eye-margin ; pronotum larger than in the 9 > '^"1^ smaller than in 

 the % of montntms, not very strongly crested and the lateral tooth short ; central 

 furrow of medial segment even broader than in the female, the posterior face with 

 rather coarse transverse striations, sides strongly striated ; first joint of medial 

 tarsi about as long as the three following united, but slightly dilated medially, 

 the apex a little pn)duced within, second joint strongly curved and produced at 

 apex within; abdomen distinctly punctured ; colored and marked as in the 9) 

 the abdominal markings, however, longer, narrow and more sinuous, and those 

 on segment four almost united. Length 7 mm. 



Colorado. The uniting of the spots on fifth abdominal segment 

 and black color of scape are good su})erficial characters in separating 

 this from iitoii.f(tiiii,s. A % specimen from Nevada, I refer with some 

 doul)t to this species ; the abdominal spots are small and con.sequently 

 widely se|)arated and the pronotum appears moi-e shai'ply dentate. 



7. Crabro bruiineipes Pack. 



Crabro bninneipes Packard, 1. c., p. 102, % . 

 9 . — Space between the eyes at base of clypeus about equal to the length of 

 joints 1 and 2 of the flagellum ; pronotum margined, but not strongly so, the 

 lateral tooth small, transverse furrow distinct though narrow ; dorsulum ante- 

 riorly rugoso-])unctate, posteriorly with strong separated punctures, those on the 

 scutellum spai-ser; mes()i)hur;e coarsely striated ; middle segment with tlu" ridge 



