some British Guiana Hymenoplera. 299 



Subfamily ANDRENINAE. 



Genus Augoohlora, Smith. 



A. graminea. F. '\ Taken while feeding on flowers 

 A. tJialia, Smith. > of " wouralli " (fish-poison plant), 

 A. calypso, Sm. J Issororo, N.W.D. 



SubfamUy PANURGINAE. 



Genus Megalopta, Smith. 



M. sodalis, Vachal. Issororo, N.W.D. This species is 

 frequently attracted to artificial light. 



Subfamily XYLOCOPINAE. 

 Genus Xylocopa, L. 



X. fimhriala, F. The commonest wood-boring bee in 

 British Guiana. The female is black and the male an 

 ochreous yellow with green eyes. The proportion of 

 females is greater than males — about 4 to 1. Both sexes 

 may frequently be seen collecting honey from a number 

 of commonly occurring flowers, especially those of the 

 large red Hibiscus and the flowers of the Pigeon Pea. 

 It possesses a powerful sting, and the flight is accompanied 

 by a loud buzzing sound. I haye neyer obseryed the 

 species in the interior. Auy dry decaying wood is utilised 

 for nesting purposes, such as rotten paling-posts or tree- 

 stumps. The softer kinds of wood are preferred. Logs of 

 wood infested by these bees soon become literally riddled 

 with their borings, and large cpiantities of frass may be 

 seen piled up at the foot of the log. If such a log is sharply 

 tapped a shrill buzzing noise may be heard caused by the 

 contained bees. A log of wood 5 feet long by 2 feet in 

 diameter on being split open was found to contain 20 

 imagos and 25-30 larvae and pupae. There were about 

 three entrance holes, and these led directly into galleries 

 bored at right angles to the grain of the w^ood. In such 

 galleries the cells are formed, usually three oi* four together, 

 neyer more. Each cell is about an inch in length and 

 about f inch in diameter. The cells are separated from 

 one another by a partition or " wad " of sawdust cemented 

 together and hardened by the bee. These partitions are 

 I inch in thickness. The galleries and cells are perfectly 

 smooth and yery neatly executed. Each cell is stocked 

 with a small, fairly solid mass consisting apparently of a 

 mixture of honey and pollen. It is a dark yellow in 



