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 ail 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. 
