10 PROCEEDINGS OF THE NATIONAL. MUSEUM. voi,. 65. 



40. Very small, anterior wing about 3 mm. long 41 



Larger 43 



41. Head and thorax brassy green; flagellum black; disk of propodeum with 



plicae on base only, apex polished (Vera Cruz, Mexico) exiguus Smith. 



Head and thorax blue; flagellum testaceous beneath 42 



42. Disk of propodeum deep blue, short, plicate; knees and tarsi yellow 



(Virginia) hortensis Lovell. 



Disk of propodeum brilliant blue, longer, with fine, somewhat wrinkled 

 plicae; legs entirely dark (New Mexico) microlepoides Ellis. 



43. Tegulae somewhat reddened; legs black; mandibles dark 44 



Tegulae very pale; knees and tarsi red; mandibles red 45 



44. Flagellum testaceous beneath; face, mesothorax, scutellum and mesopleurae 



brassy (Colorado) mactus, new species. 



Flagellum hardly paler beneath; not thus brassy (Colorado). 



pensitus, new species. 



45. (The following are very similar in size, color, punctation, etc.): 



Third joint of antennae somewhat longer than second 46 



Third joint of antennae hardly or no longer than second 47 



46. Disk of propodeum plicate (Colorado) accentus, new species. 



Disk of propodeum rugose (New Mexico) incompletus Crawford. 



47. Abdomen entirely black, punctured (Colorado) mollis, new species. 



Abdomen with piliferous punctures only, apical margins of segments 



testaceous 48 



48. Mesothorax sparsely and delicately punctured; disk of propodeum plicate 



(New Mexico) merosus, new species, 



Mesothorax more closely punctured; disk of propodeum rugose 49 



49. Disk of propodeum crescentic, with irregularly anastomosing rugae reaching 



the apex; legs and abdomen brown (Virginia) malinus, new species. 



Disk of propodeum long, rugae reaching the apex which is polished; abdomen 

 and legs black (Iowa) insolitus, new species. 



DESCRIPTIONS OF NEW SPECIES. 



HALICTUS (CHLORALICTUS) OLIVARIL'S, new species. 



Female. — About 8.5 mm. long; dark olive green; pubescence pale; 

 facial quadrangle longer than broad; front closely punctured, the 

 punctures becoming more scattered on the sides of the face; antennae 

 brown, becoming bright ferruginous at the apex of the flagellum; 

 orbits converging slightly below; clj^peus black, coarsely punctured; 

 supraclypeal area brassy, sparsely punctured. Mesothorax golden 

 green, very closely punctured; parapsidal grooves quite indistinct; 

 scutellum closely punctured; disk of propodeum appears rugose, but 

 is covered with finely wrinkled anastomosing rugae making an irreg- 

 ular reticulate surface; truncation well defined laterally; tegulae pale 

 testaceous, impunctate. Abdomen ovate, without distinct hair bands, 

 but with pale pubescence covering the segments; apical margins of 

 segments testaceous. Wings yellowish, faintly dusky; anterior wing 

 about 6 mm. long; stigma and nervures pale testaceous; basal ncrvure 

 very strongly bent; thh-d submarginal cell strongly contracted 

 above, more than twice as long as second on marginal; second sub- 

 marginal higher than broad, receiving first recurrent nervure very 



