2iZ G. H. BISHOP 
into the vagina of the queen, and its retention within it when 
everted. Certain conformations of the penis have been described 
with considerable ingenuity and in great detail as ‘fitting,’ or 
formed so as to lodge in, corresponding regions of the bursa or 
vagina, as the eversion of the copulatory organ proceeded. The 
impossibility of observing copulation, which takes place high 
in the air, makes such inferences the best evidence available 
as to the manner of coitus. 
While the detailed description of this correspondence between 
the anatomy of queen and drone is irrelevant to the object of 
this paper, and has been described by other writers, a brief 
analysis of the process of coition is necessary to the interpre- 
tation of some of the data. Two points discussed in recent liter- 
ature seem to have been inadequately treated. The functioning 
of the pneumophyses (fig. 2, C, ¢) has not been satisfactorily 
analyzed, and the extent of the eversion of the copulatory organ 
—whether this takes place up to the bulb of the penis (fig. 2, B) 
or whether the bulb also everts (fig. 2, C)—is open to question; 
as is also the distance to which it enters the vagina of the queen. 
In figure 1, C, is drawn, uneverted, the bulb of the penis of 
the drone to the same scale as that of the queen’s organs in 
figure 1, B, and from the same lateral aspect. _ It may be observed 
(fig. 2) that as the penis extrudes from the male genital aperture 
the first portion to evert, after the short proximal tubular section, 
will be the penumophyses (e). If queen and drone are in position 
for coitus (tip of drone’s abdomen inserted between the anal 
plates of the female) these pneumophyses presumably evert into 
the paired bursal pouches opening from the copulatory bursa 
by slits on either side of and below the vaginal orifice (fig. 1, 
A and B, b). The hypothesis is hardly tenable, however, though 
it has been presented, that their function is to hold the organ 
momentarily in the queen’s bursa while further eversion of the 
organ takes place. In the first place, their eversion coincides 
with a violent contortion of the drone’s abdomen (when pro- 
trusion of the organ is artificially induced, and presumably in 
the natural act), which would render any holding function for 
such soft and pliant organs not only relatively insignificant, but 
