520 



Saw-flies, Gall-flies, Ichneumons, 



are no longer provided with a pollen-basket (concave smooth surface 

 bounded by lines of long stiff incurving hairs) and by the absence of 

 this arrangement they may always be distinguished from the true bumble- 

 bees. There is no working caste, infertile female workers, with these 

 Psithyridae, each species being represented by males and females only. 



At the head of this line of specialization among the bees, that is, the 

 development of the communistic tendency, stand the two genera of honey- 

 bees, Melipona and Apis. The numerous species of Melipona are restricted 



FIG. 725. Comb of the tiny East Indian honey-bee, Apis florea. 

 (After Benton; one-third natural size.) 



to tropical regions; some are very small, the so-called "mosquito-bees," and 

 in all the sting is blunted and apparently never used as a weapon. The life- 

 history of no one of the species has been fully made out, and there is some 

 doubt as to whether each community some of the nests are known to include 

 an enormous number of individuals has but a single queen that is, single 

 egg-laying female or not. Of the other genus, Apis, there are but few 

 species, the best known being the common hive-bee, A. mellifica, which 

 extends naturally over all the northern half of the Old World and from there 

 has been introduced into nearly all the countries of the globe. In its long 

 domestication several varieties or races have been created by artificial selec- 

 tion, the more familiar ones being the German or black race, the Italian 

 or amber race, and the Carniolan or striped race. 



