FERTILIZATION OF THE FEMALE 



505 



homologous with the egg-producing division of the female ovarian tubes, points 

 back to hermaphroditic ancestors. And Heymons suggests that the frequent 

 occurrence of hermaphroditism in insects probably confirms this view. 



The bursa copulatrix. The copulatory pouch in most insects is 

 a special cup-shaped appendage of the vagina adapted for the 

 reception of the male organ during sexual union. Its mode of 

 formation in the cock- 

 roach is thus described 

 by Haase : 



"By the retreat of the 

 female sexual aperture, 

 situated in the 8th ven- 

 tral plate, a considerable 

 space, the genital pouch, 

 is produced ; this is 

 formed chiefly by the 

 extended connective mem- 

 brane between the elon- 

 gated 7th and 8th ventral 

 plates. This serves for 

 the development of the 

 egg-cocoon, which is re- 

 tained by the internal 

 appendages of the pos- 

 terior gonapophyses." 



The fertilization of the 

 female takes place once 

 for all a long time pre- 

 vious to oviposition; the 

 semen in the receptacu- 

 lum seminis passes out as 

 the eggs slip down the 

 egg-passage, and a sper- 

 matozoon gains entrance 

 into the interior of the egg through the micropyle. In (Ecanthus, 

 according to Ayers, fecundation probably takes place while the egg 

 is passing into the vagina, "since it is hardly possible that the 

 male element could gain access to the follicles before the chorion is 

 secreted." 



In the Lepidoptera, as has been stated, the copulatory pouch opens 

 separately from the opening of the oviduct (vagina), but a slender 

 canal connects the pouch with the vagina (Fig. 310, be). The outlet 



FIG. 479. Abdomen of queen bee, under side, x 8: 

 P, petiole ; o, o, ovaries ; hs, position filled by honey-sac ; 

 ds, place through which the digestive canal passes ; od, 

 oviduct ; co.d, common oviduct ; E, egg passing oviduct ; 

 s, spermatheca ; i, intestine ; pb, poison-bag ; p.fj, poison- 

 gland ; st, sting ; p, palpi. B, vestigial ovaries of ordinary 

 worker ; t,p, vestigial spermatheca. C, partially developed 

 ovaries of fertile worker ; sp, vestigial spermatheca. 

 After Cheshire. 



