24 THE HUMBLE-BEE a 
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.* 
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 Hoffer’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 Arztish Bee Journal for Dec. 14, 
1911, and ‘‘ Further Notes on how the Corbicula is loaded with Pollen,” in the 
B.B J. for April 11, 1912. In the latter article the receiver is named the 
excipula (Lat, receptacle), and the entrance to the corbicula the “men (Lat. 
threshold). In Bombus confisus, 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 Bomébus lapidartus, terrestris, 
lucorum, pratorum, lapponicus, latretllellus, and distinguendus the auricle is 
hairy on the inner side ; in all the other British species it is bare there. 
