24 THE HUMBLE-BEE 



ii 



along the margin bordering on the corbicula, where 

 it is finely striate, the little furrows and ridges 

 running in the direction in which the pollen moves. 



The auricle bears a tuft of hairs which helps to 

 guide the pollen on to the corbicula. 



Long hairs spring from either side of the entrance 

 to the corbicula and form over it an arch which 

 helps to support the accumulated mass of pollen 

 without interfering with the delivery of fresh pollen 

 from below. The arch is also of service in guiding 

 the pollen on to the corbicula. 1 



Humble-bees working on the white dead nettle 

 may be seen brushing the pollen out of the hairs on 

 the front of the thorax, where it chiefly gathers, 

 with the middle pair of feet, the instrument used 

 being the metatarsus or basal joint of the foot, 

 which is modified into a brush like the metatarsus 

 of the hind leg. I have occasionally found a minute 

 ball of moistened pollen in the mandibles, which 

 seems to support H offer's view that the pollen is 

 moistened in the mouth. 



The wax of the humble-bee is much softer and 



1 See my paper, " How pollen is collected by the Social Bees, and the part 

 played by the Auricle in the process," in the British Bee Journal for Dec. 14, 

 191 1, and " Further Notes on how the Corbicula is loaded with Pollen,"' in the 

 B.B.J, for April n, 1912. In the latter article the receiver is named the 

 excipula {Lai. receptacle), and the entrance to the corbicula the limen (Lat. 

 threshold). In Bombus confusus, a native of Central Europe, the obstructing 

 hairs on the limen are reduced to one ; in the honey-bee the fluff on the limen 

 is scanty, and there are no obstructing hairs, except one, situated some way 

 inside the entrance. In the humble-bee the working surface of the auricle 

 is finely rugose, but in the honey-bee it is covered with pointed teeth inclining 

 in the direction that the pollen moves. In Bombus lapidarius, terrestris, 

 lucorum, pratorum, lapponicus, latreillcllus, and distinguendus the auricle is 

 hairy on the inner side ; in all the other British species it is bare there. 



