NOTES ON THE BEE-GENUS HALICTUS. 207 



submarginal cell of the long type, but shorter than usual ; the 

 spur has few large teeth. This insect is clearly related to H. 

 fasciatus. H. cariniventris, Mar., from Buda, 29th May, 1886, is 

 a green species, with the abdomen covered with ochreous hair as 

 in various American Anthophorids ; the third submarginal cell is 

 quite of the long type, though not very long. In H. scahiosce and 

 H. maculatiis the teeth of the spur are short and triangular, so 

 that the spur becomes coarsely serrate, just as in the American 

 species referred to Lasioglossum (Robertson says for these "finely 

 serrate," but under a high power it appears coarse enough). 



Eobertson not only separates the species with a short third 

 submarginal from Halictus, but divides these into several groups, 

 of which Lasioglossuin, Evylceus, and Choralictus occur in Europe 

 as well as America. 



Lasioglossum, as thus restricted, includes comparatively large 

 black species with abdominal hair-bands ; species re- 

 sembling Halictus proper except in the venation. 

 EvylcBus and Chloralictus are ordinarily smaller, the abdomen 

 commonly pubescent or pruinose, but not exhibiting 

 definite hair-bands, and the second transverso-cubital 

 nervure is more or less weak. The last character, on which 

 Robertson lays stress, seems to me of doubtful value. The 

 only difference between Evylceus and Chloralictus is that 

 the former is black, the latter green or blue, or at least 

 partly so. 

 If all these characters are held to be generic, we need more 

 generic names. Thus, using the colour and spur, Halictus pro- 

 per may be divided thus : — 



(1.) Colour green ; spur pectinate — e.g.virescens. 

 (2.) Colour black ; spur pectinate — e. g. patellatus. 

 (3.) Colour black ; spur serrate — e. g. scahiosce. 



Again, Lasioglossum divides thus : — 



(1.) Colour black ; spur pectinate — e. g. xanthopus. 



(2.) Colour black ; spur serrate — e. g. coriaceus. 



Even the character of the third submarginal cell fails us, as 

 witness the following species : — 



H.fasciatellus, Schenck, has the third submarginal between 



the long and short types, a slight double curve on outer 



margin. 

 H. l(Bvigatus, Kirby, has a very large third submarginal, with 



a faint indication of a double curve, but its general shape is 



more as in Lasioglossum. The spur has numerous short 



strong teeth. 

 H, zonulus, Smith, has the third submarginal very large, 



twice as broad below as the second, but its outer margin 



is regularly and gently arcuate. The spur is minutely 



but distinctly beaded. 



