Dec, 1907] Crawford: Notes on Halictus. 185 



Surface of metathorax not concealed by pubescence 25 



24. Mesothorax shiny, sparsely punctured, not distinctly lineolated. 



am^iistior Cockerel 1. 

 Mesothorax dull, closely punctured, distinctly lineolated robertsoni Crawford. 



25. Inner spur of hind tibiae simple, or with saw-like teeth, or very oblique teeth 



hardly longer than broad at base 26 



Inner spur with long spines, the basal ones at least being several times as long as 

 broad at base 31 



26. Mesothorax very dull from lineolation ; facial quadrangle longer than broad. 



dasiphorir Cockerell. 

 Mesothorax somewhat shiny, facial quadrangle as broad or broader than long. ..27 



27. Base of metathorax coarsely rugose ; truncation coarsely sculptured. 



arctiatiis Robertson. 

 Base of metathorax finely wrinkled ; truncation not coarsely sculptured ■...28 



28. First abdominal segment closely, strongly punctured, size large, about 9 mm. 



robustiis Crawford. 

 First segment sparsely weakly punctured, smaller 29 



29. Wings clear hyaline, abdomen brownish, apical margins broadly whitish. 



amicus Cockerell. 

 Wings dusky, abdomen darker 30 



30. Face above antennre closely punctured ; metathorax finely irregularly wrinkled. 



latifrons Crawford. 

 Face above antennae sparsely indistinctly punctured ; metathorax with fine irreg- 

 ularly longitudinal rugulce .peco^ensis Crawford. 



31. Inner hind spur with many long teeth .pectinatus Robertson. 



Inner hind spur with 2-7 teeth 32 



32. Antennae red beneath ; abdomen brown, the first segment strongly transversely 



striate subobscurns Cockerell . 



Antennas darker beneath, abdomen darker, first segment at most finely trans- 

 versely lineolate 33 



33. First abdominal segment closely distinctly punctured all over. 



fedorensis Crawford. 

 First segment impuncate or sparsely punctate apically 34 



34. Stigma brown, usually very dark 35 



Stigma honey color 38 



35. Base of metathorax finely wrinkled, rounded behind 36 



Base of metathorax rugose, ending at a carina of enclosure 37 



36. Wrinkles of metathorax more numerous, punctures of mesothorax sparser, weaker, 



punctures of faceless strong qitadrimaculahis Robertson 



Wrinkles of metathorax less numerous, punctures of mesothorax closer, stronger, 

 punctures of face stronger divergeus Lovell. 



37. Rugse of metathorax stronger, enclosure semicircular, distinct, punctures of meso- 



thorax strong, coarser .pectoralis Sm i th . 



Rugae of metathorax weaker, enclosure indistinct, punctures of mesothorax 

 finer, sparser .pectoraloides Cockerell . 



38. Larger species over 8 mm 42 



Smaller species not over 7 mm 39 



I 



