24 



HEREDITY AND SEX 



union possible. In some types mating must occur for 

 each output of eggs, but in other cases the sperm is 

 stored up in special receptacles connected with the ducts 

 of the female. From these receptacles a few sperm at 

 a time may be set free to fertilize each egg as it passes 

 the opening of the receptaculum. In the queen bee 

 enough sperm is stored up to last the queen for five or 

 six years and enough to fertilize a million eggs. 



^' / !*•■■ ? 



Fig. 10. — Squid : Two upper right-hand figures illustrate two methods 

 of copulation. Lower right-hand figure dissected to show spermatophore 

 placed in mantle cavity of female. Left-hand figure (below), spermatophore 

 pocket behind mouth of male; upper figure, section of same. (After Drew.) 



There are a few cases where the transfer from the 

 male to the female is brought about in a different way. 

 The most striking cases are those of the squids and 

 octopi, and of the spiders. 



In the squid, the male and female interlock arms 

 (Fig. 10). The male takes the packets of sperm (that 

 are emitted at this time from the sperm-duct) by means 

 of a special arm, and transfers the packets either to a 



