168 
Psyche 
[December 
addition of this wax-like substance on the rim of the cup. 
Thus in Nest B, 16 empty cocoons which had been used at 
one time or another as storage vats had had their capacity 
increased by extensions which varied from one-eighth inch 
to three-fourths inch. Two old cocoons completely filled with 
honey were tightly sealed with lids of wax. The largest pot, 
constructed entirely of wax, was in Nest B, and measured 
one inch in height by a half-inch in diameter. In both nests 
were several of these cocoon-vats that had remnants of pol- 
len or honey, and in some cases they were half full of food 
at the time the nests were taken. In both nests some of the 
old cocoons had been partly bitten away, evidently by the 
workers, but why it had been done or what the bits of ma- 
terial had been used for is not known. 
There were no males in the nests, neither were there any 
parasites or messmates, except for an unknown moth larva 
and an unknown moth cocoon among the cocoons. 
On the whole, except for the tendency to slightly larger 
colonies, the life history of Bomhus medius differs but little 
from that of our Missouri Bomhus americanorum. 
