HALICTUS. 37 



Head with a longitudinal striation above the antennae ; the clypeus 

 shining, and with a few strong punctures ; mandibles rufo-piceous, 

 with their tips black ; the fiagellum of the antennas fulvous beneath. 

 Thorax black at the sides and beneath ; wings hyaline and irides- 

 cent, the nervures and tegulae rufo-testaceous ; legs pale ferrugi- 

 nous. Abdomen dark rufo-piceous in the middle, the sides bright 

 ferruginous, smooth, and shining ; the apical segment pale ferrugi- 

 nous, and with pale pubescence. 



Hab. Champion Bay. 



22. Halictus agilis. 



Male. Length 3|-4 lines. — Brassy green. The head very finely and 

 closely punctured ; the face with pale pubescence, that on the 

 cheeks white ; the head as wide as the thorax and rounded, with 

 the clypeus produced moderately, its anterior margin narrowly 

 yellow ; the flagellum, except one or two of the apical joints, ful- 

 vous beneath. The mesothorax and scutellum finely punctured ; 

 the base of the metathorax with irregular striation ; wings clear 

 hyaline, the nervures and tegulae pale rufo-testaceous ; all the 

 tarsi and tibiae, as well as the anterior and intermediate femora, 

 pale ferruginous ; the coxae, trochanters, and posterior femora 

 black or rufo-piceous, with an aeneous tinge. Abdomen ovate, 

 shining and finely punctured, the basal margin of the second 

 segment and the apical margin of the following with pale pube- 

 scent fasciae. 



Hab. Mexico, Oajaca. 



23. Halictus exigims. 



Female. Length 2 lines. — Head and thorax dark green; abdomen 

 black, with the margins of the segments rufo-piceous. Head 

 rather large, shining and finely punctured, rounded, with the man- 

 dibles ferruginous and the flagellum fulvous beneath. The meso- 

 thorax shining and finely punctured ; the base of the metathorax 

 smooth and shining, with a few faint, short striae at the extreme 

 base ; wings hyaline and iridescent, the tegulae and nervures pale 

 testaceous; the anterior tibiae and all the tarsi rufo-testaceous, 

 with a little pale fulvous pubescence. Abdomen shining, and very 

 delicately punctured beyond the basal segment. 



Hab. Mexico. 



24. Halictus vagans. 



Female. Length 3 lines. — Shining brassy green, the abdomen ob- 

 scurely so beyond the basal segment. The head closely and finely 

 punctured, rounded, with the clypeus slightly produced and of a 

 purple colour, the face thickly covered with short pale ochraceous 



