166 AMERICAN HYMEXOPTERA. 



Another specimen of angustior was taken at Mesilla, New Mex., 

 May 9, 1896, on 3Ialacothrix fendleri Gray in the Woodlands orchard. 

 This has the abdominal bands lacking, except for patches at the 

 extreme sides, even these ill-developed, and thus looks very like 

 pectoraloides, indeed, but it is at once separated by the duller meso- 

 thorax and first abdominal segment. The resemblance to pectoral- 

 oides is further increased by the abdominal segments being retracted, 

 so that the abdomen loses its elongate form. 



(B.) Small, or moderately small black species, without continuous 

 hair-bauds on the abdomen, or only one band continuous. 

 (1.) Females. 

 (a.) Abdomen black, the segments not margined with testace- 

 ous ; fii'st segment impunctate ; lateral white hair-patches 

 present ; stigma piceous. 

 Halictus pectoraloides Ckll. 



A very abundant species, taken as follows : 



(a.) Las Cruces, New Mex., on Sisymbrium, April ; on Solanum 

 July ; on Aphanostephus ramosmimus (formerly reported in error 

 as Erigeroa strigosus) April 26 ; thirteen on Melilotus indica College 

 Farm, May 1 ; on white Aster June 16 ; two on Salix May 3, 1895, 

 and others on Salix May 'i, 1896 ; on Biscutella wislizenii March 9 ; 

 on supposed Flaveria August 25. 



(b.) Mesilla, New Mex., on Actinella riehardsonii May 10, 1896. 

 (c ) Roswell, New Mex., one on plum April 14, 1896. 

 (d.) Santa Fe, New Mex., August 5, one only. It appears to be 

 rare at Santa Fe. 



For the supposed S see below. 



(b.) Abdomen rather brownish (piceous), the hind margins of • 

 the segments more or less testaceous, first segment more or 

 less punctured, if only microscopically ; stigma honey color. 

 a. Flagellum more or leos testaceous beneath, tarsi rufous, first 

 segment of abdomen transversely striate. 

 Halictus subobscurus Ckll. 



Not very connnon. Las Cruces, April, on Sisymbrium ; also one 

 on August 14. Santa Fe, one on July 25, 1895. The last men- 

 tioned shows hair-bands on bases of segments 2 and 3, that on 2 

 interrupted. 



(/3.) Flagellum wholly dark, tarsi dark, first segment of abdomen 

 not transversely striate. 

 Halictiis lusorius Cress. 



One from the west fork of the Gila River, New Mexico, July 16 



