Mr. Hunter's Observations on Bees. 185 
back, having a vast number of air-vessels passing into them, 
and ramifying upon them. They are of a pale yellowish 
colour. From their lower ends pass down ducts, which may 
be called vasa deferentia, and which enter two bags : these 
two bags, into which the vasa deferentia enter, are probably 
reservoirs for the semen. From the union of these two bags 
passes out a duct, which runs towards the termination of the 
abdomen, and ends in the penis. These three parts, namely, 
testicles with their ducts, the two bags, and the duct arising 
from them, which I have termed urethra, are all folded on 
each other, so as to appear as one body. 
In the introduction to this account of bees I observed, that 
several things in their ceconomy might escape us if we con- 
sidered them alone, but might be made out in other insects : 
an instance of this occurs in the impregnation of the female 
bee. The death of the males in the month of August, so that 
not one is left, and yet the queen to breed in the month of 
March, must puzzle any one not acquainted with the mode 
of impregnation of the females of most insects. Insects, re- 
specting the males, are of two kinds: one, where the male 
lives through the winter, as well as the female ; and the other, 
where every male of that species dies before the winter comes 
on; among which may be considered, as a third, those where 
both male and female die the same year. Of the first, I shall 
only give the common fly as an instance ; of the second, I shall 
just mention all of the bee tribe ; and the third may be il- 
lustrated in the silk-worm. The mode of impregnation in 
the first, is its being continued uninterruptedly through the 
whole period of laying eggs; while in the second, the copu- 
lation is in store; and, in the third the female lays up, bv 
MDCCXCI 1. B b 
