274 THE HUMBLE-BEE 
nest of ruderatus had six young larve, varying from the 
size of a lettuce seed to that of a mignonette seed in one 
cell, 3 eggs in another cell, and 5 eggs in another. 
How Pollen is collected (pp. 20 to 24).—Many varie- 
gated loads of pollen collected by Bomdz, consisting of 
two or more kinds, were examined during 1912, and they 
showed clearly not only that the pollen is pushed into 
the corbicula in the way explained on p. 22, but how the 
load is built up. 
About 40 per cent of the loads brought home by a 
colony of terrestris between July 15 and July 25 could be 
5, orange 
6, yellow 
7) orange 
8, yellow 

ENTRANCE ro CORBICULA tlie iis: |: 
FIG. 34. 
A, Shallow. load of pollen in the left corbicula of a worker of Bombus agrorum 
captured at dead-nettle on July 4, 1912. 4B, Section through a full load of 
pollen in the left corbicula of a worker of B. ¢errestris taken on entering its 
nest, July 23, 1912. 
The layers of the different kinds of pollen are numbered in the order in which 
they were collected. Had the agrorum worker gone on collecting and gathered a 
full load, the pollen shown in its corbicula would have occupied the region referred 
to as ‘1, yellow” in Fig. B. 
seen at a glance to consist of two kinds of pollen; ina 
few of these, on closer examination, three or more kinds 
were detected. 
Pollen-primers (p. 43).—S. latrecllellus was considered 
to be a pollen-primer because pollen was found under the 
eggs in a nest in an advanced stage examined in IQII. 
