\ 



' BEKS OF GREAT BRITAIN. 91 



known. It appears in the month' of April; the large-headed 

 males have a very ferocious aspect. 



50. Andrena albicrus, 



A, atra, cinereo-villosa ; thorace fulvo; abdomine ovato, pilosulo, 

 strigis tribus albis ; scopa versicolori. 



Melitta albicrus, Kirbj/^ Mon. Jp. AngL ii. 156. 96 ^ ? . 

 Melitta barbilabris, Kirhy, Mon, Ap. AngL ii. 151. 91 c? var. 

 Andrena albicrus, Smith, ZooL v. 1924. 59. 



Female, Length 5-51 lines. — Black; the face on each side and 

 the vertex have a little pale fulvous pubescence^ the channel on 

 each side of the face covered with a fulvous pile ; the flagcUum 

 nigro-piceous beneath. Thorax : the disk thinly clothed with 

 fulvous pubescence, on the metathorax and sides it is paler ; 

 the wings subhyaline, the nervures and tegulse rufo-piceous ; 

 the legs have a cinereous pubescence ; the scopa fuscous above 

 and silvery-white beneath ; the floccus white. Abdomen ovate, 

 smooth and shining, the second, third and fourth segments have 

 a narrow white marginal fringe, the two first usually inter- 

 rupted; the apical fimbria fuscous; beneath, the margins of 

 the apical segments have a narrow white fringe, the segments 

 having some longer scattered silvery pubescence. B.M. 



Male. Length 4-5 lines. — Black; having a long hoary pubes- 

 cence on the head, thorax and legs ; that on the disk of the 

 thorax tinged with ochraceous, that on the clypeus being snow- 

 white and glittering, forming a beard, which hides the labrum. 

 Abdomen ovate-lanceolate, having a thinly scattered cinereous 

 pubescence ; the margins of the segments depressed, a little 

 pale glittering pubescence at the apex. B.M. 



This species appears about the middle of May, and forms 

 large colonies. I have frequently observed the sexes in coitu. The 

 species is generally distributed, and is very plentiful on Ilamp- 

 stead Heath ; it is also very numerous about Charlton, Black- 

 heath, &c. It has been taken in Yorkshire in the month of 

 July; at the sides of a sandy road on the top of WooUey Edge 

 near Wakefield are immense colonies; there it swarms in count- 

 less numbers ; they occur in every flower of a species of Hawk- 

 weed, with which the sides of the lane are bordered. 



