12 



HYMENOPTERA 



The hind-legs of bees are very largely used in the industrial 

 occupations of these indefatigable creatures; one of their chief 

 functions in the female being to act as receptacles for carrying 

 pollen to the nest: they exhil)it, however, considerable diversity. 

 The parts most modified are the til)ia and the first joint of the 

 hind-foot. Pollen is carried l)y other parts of the body in many 

 bees, and even the hind-leg itself is used in different ways for the 

 , purpose : sometimes the outer face 



of the tibia is highly polished and 

 its margins surrounded l)y liair, in 

 which case pollen plates are said to 

 exist (Fig. 6, A) ; sometimes the first 

 joint of the tarsus is analogous to 

 the tibia lioth in structure and 

 function ; in other cases the hind- 

 legs are thick and densely covered 

 with hair t)iat retains the pollen 

 between the separate hairs. In this 

 case the pollen is carried home in a 

 dry state, while, in tlie species with 

 pollen plates, the pollen is made 

 into a mass of a clay-like consist- 

 ence.^ The legs also assist in arrang- 

 ing the pollen on the other parts of 

 the body. The males do not carry 

 pollen, and though their hind-legs 

 are also highly modified, yet the 



middle-leg (trochanter with part of jnodificationS do UOt agree with 

 coxa and oi lemur) with ])unuose '^ 



hairs and grains of pollen ; C, one tllOSe of the female, and their fuUC- 



hair bearing pollen-grains. ;• ■ ii ii-Tj- i 



" ' " tions are m all probability sexual. 



The parasitic bees also do not carry pollen, and exhibit another 

 series of structures. The most interesting case in this series of 

 modifications is that found in the genus Ajns, where the liind-leg 

 of male, female, and worker are all different (Fig. 25) ; the limb 

 in tlie worker being higlily modified for industrial purposes. 

 This case has been frecjuently referred to, in consequence of the 

 difficulty that exists in connection with its heredity, for the 



Fig. 6. — A, Worker of the honey-bee 

 {Ajns7neUi/ica), with pollen plates 

 laden ; B, basal portions of a 



^ The mode of wetting the pollen is not clear. Wolff says it is done by an exu- 

 dation from the tibia ; H. Miiller by admixture of nectar from the bee's mouth. 

 The latter view is more proba])ly correct. 



