78 ANDEENID^B. 



Genus 6. HALICTUS, Latr. 



Apis (pt.), Linn. Syst. Nat i. 953 (1766). 

 Hylseus (pt.), Fair. Syst. Mitii. 302 (1793). 

 Melitta (pt.), Kirby, Man. Apum Angl. i. 134 (1802). 

 Prosopis (pt.), Fabr. Syst Piez. 293 (1804). 

 Megilla (pt.), Fabr. Syst Piez. 328 (1804). 

 Halictus, Latr. Hist. Nat. xiii. 364 (1805). 

 Lasioglossuin, Curtis, Brit. Fnt x. 418 (1834). 



Head subtriangular, scarcely as wide as the thorax ; the ocelli in 

 a curve on the vertex ; the antennae, geniculated, the scape fully 

 half the length of the nagellum, the latter filiform • the clypeus more 

 or less produced ; the tongue acute, as are also the paraglossce, which 

 are about two thirds of the length of the tongue ; the labial palpi 

 four-jointed, the basal joint as long as the two following, the three 

 apical joints gradually slightly decreasing in length; the maxillary 

 palpi 6-jointed, the basal joint shortest, the following joints gradu- 

 ally decreasing in length to the apical one ; the labrum of the females 

 transverse, furnished with a carinated appendage in front, densely 

 fringed with pubescence at its margins. Thorax ovate ; the ante- 

 rior wings with one marginal cell, narrowed to and acute at its 

 apex ; three submarginal cells, the first as long as the two following 

 united, the second subquadrate and receiving the first recurrent 

 nervure near its apex, the third submarginal narrowed towards 

 the margiual and receiving the second recurrent nervure at about 

 one third of its length from the apex ; the posterior legs have a 

 floccus of pubescence on the coxae and trochanters, and a dense pol- 

 liniferous scopa on the tibiae. Abdomen ovate, the apical segment 

 with a central longitudinal rima. 



The males have the antennae elongate, usually longer than the 

 thorax; the clypeus frequently much produced and more or less 

 yellow at the apex ; the abdomen cylindric and elongate. 



The economy of this genus of Andrenidse does not appear to have 

 been ascertained previous to my own observations being published 

 in the year 1850 : it is so remarkably different from that of all other 

 solitary bees, except of those belonging to the genus Sphecodes, that 

 I am surprised it had escaped the researches of my predecessors who, 

 like myself, " have loved to hear the wild bee's hum." It will be 

 observed that the females of Halictus and Sphecodes make their ap- 

 pearance in June, and are to be found from that time until late in 

 the autumn; but no males of these genera will be observed until 

 long after the appearance of the females. My observations on a 

 colony of H. morio will serve as the history of the whole genus, 

 making allowance for the different periods of their appearance. 

 " Early in April the females appeared, and continued in numbers up 

 to the end of June ; not a single male was to be found at any time: 

 during the month of July scarcely an individual could be found ; a 

 solitary female now and then might be seen, but the spring bees had 

 almost disappeared. About the middle of August the males began to 



