Beeeptaeulum Seminis of Bees and Wasps. By F. B. Cheshire. 7 



for fertilization, the muscle g by contraction * would lift the plate 

 lying above and between o and h, to which by a complex tendon it is 

 attached. Into the cavity o thus opened spermatozoa would pass. 

 The two sphincters at the same moment relaxing, an outflow of 

 glandular secretion, as indicated by the arrow, would be ready to 

 sweep the spermatozoa towards their destination in the common 

 oviduct, and all would be at once driven on by the appendicular 

 sphincter first contracting, followed in order by the second 

 sphincter and muscles marked h, when the repose condition would 

 again be established. 



A most remarkable adaptation here arises. The spermatozoa 

 yielded by the drone are probably about 4,000,000 in number ; 

 but these need to be economically utilized, as if they were shot out 

 haphazard, they would be exhausted long before the queen's death, 

 when she would breed of course drones only (a circumstance which 

 does actually, although somewhat exceptionally, arise when queens 

 run on without accident to the ripe old age of four or five years) ; 

 but the duct h h through which they pass, I find to be the centre 

 of another gland I I, which seems to the present to have entirely 

 escaped attention. This gland is, no doubt, excited to secretion by 

 the presence of the spermatozoa, just as food excites our salivary 

 glands to the secretion of saliva, and the stomach to the secretion 

 of gastric juice. Spermatozoa thickly present will cause the 

 addition of large quantities of fluid which will dilute and more 

 widely separate them. Their absence (for this gland is most richly 

 provided with nerve-twigs, which send numerous loops to the 

 muscles previously described and to the ganglion i seen lying under 

 the muscle g) will yield the action which will send a new contingent 

 forward as I have described, and so they come to be paid out with 

 some regularity. The necessity for this regularity will be better 

 appreciated if it be remarked that a prolific queen will lay 1,500,000 

 eggs, each about 1 • 8 mm. long, " 4 mm. in diameter, and that 

 these would fill, if systematically packed, a half-pint measure. 

 Deducting a few thousand for drones, the remainder would each 

 require an independent fertilization, and for this work probably 

 not more than 4,000,000 and often very many less spermatozoa 

 will be at command. We shall presently see that the number of 

 spermatozoa and the size of the receptaculum appear to be propor- 

 tioned to the laying capabilities of the insect, and hence in every 

 case some such mechanism as we have been examining will be a 

 necessity. In the common wasp, for example, the fecundity is 

 much less than in the hive bee, but the spermatheca is much smaller, 

 the capacity of that of the latter insect being about forty times 



* I am fully satisfied that these muscular changes would be all produced by 

 reflex action. 



