138 THE ANATOMY OF THE HONEY BEE. 



holds about 4,000,000 spermatozoa, and therefore, allo\yiiig; for drones, 

 he conchides that there can not be more than four sperm-threads given 

 to each female egg. But Breslau, figuring from the size of the sperm- 

 bundle taken into the duct for each egg, states that each egg is 

 actually given 75 to 100 spermatozoa. We feel that the latter calcula- 

 tion must be much more reliable than that of Cheshire because it 

 is based on an actual observation of the size of the sperm mass de- 

 livered to the egg. Moreover, the myriads and myriads of tiny 

 spermatozoa contained in the spermathecal sac make any attempt 

 at a calculation of the number look absurd, and we can not believe 

 that it is possible to even approximate the number present. Fur- 

 thermore, as Breslau states, 100 spermatozoa make such an excessively 

 small bundle that it requires a most effective and perfect apparatus to 

 deliver even this number with anything like exactness — it is incon- 

 ceivable that a mechanism could be perfect enough to give out only 

 4 or 5 or even 7 at a time. 



On the floor of the vagina, opposite the opening of the spermathecal 

 duct, is a free flap provided with muscles, which is so situated 

 that when elevated its end fits into the opening of the duct above. 

 Leuckart (1858) explained this flap as a contrivance for holding the 

 passing egg tight against the upper vaginal wall so that its aperture 

 through wdiich the spermatozoa is received, called the micropyle, would 

 come against the opening of the duct and thus insure fertilization. 

 Breslau, on the other hand, does not think the flap in question has 

 any such function and he regards it as a valve wdiich by fitting into 

 the orifice of the spermathecal duct closes the latter and so prevents 

 the pump from sucking up the contents of the vagina at the same time 

 that it sucks a bundle of spermatozoa out of the sac. Since, however, 

 the flap is on the floor of the vagina and is pressed down by the passing 

 egg it is not clear how it can at such a time act as a valve to close the 

 orifice of the duct in the dorsal wall, since the pump is supposed to 

 work by reflex action as the egg is entering the vagina, though, of 

 course, it may so function before the egg has gone far enough to 

 intervene between it and the duct opening; but it would certa.inly 

 seem that a valve to close the latter, if needed at all, would be de- 

 veloped in the dorsal wall of the vagina in connection with the orifice 

 itself. Furthermore, a collapsible tube like the spermathecal duct, 

 even though lined with chitin, should automatically close at its 

 lower end when a suction force is applied at the upper end. 



Finally, Breslau attriV)utes to the sperm pump not only the func- 

 tion of delivering a definite mass of spermatozoa to each egg, but also 

 that of sucking the spermatozoa up from the vagina of a newly fer- 

 tilized queen into the spermathecal sac. He does not seem now to see 

 in the valve any obstacle to such an action. The spermatozoa are 

 usually supposed to make their way up the duct by their own vibra- 

 tory motion. 



