THE MALE REPRODUCTIVE ORGANS 



487 



of the integument of the 2d, 3d, and 4th abdominal segments. In the 2d to 5th 

 segments are situated tubes which open in the cavity of the body with funnel- 

 like ends, so that the ducts have a close resemblance to the segmental organs of 

 worms. (Nassouow.) 



Among the winged insects the reproductive organs of the cricket 

 (Fig. 466) are perhaps as simple as any. The testes are separate, 

 and the vasa deferentia very long. The seminal vesicles bear 

 numerous large and short utricles (utriculi majores and breviores'), 

 the penis being simple and dilated 

 at the end ; while in Pliyllodro- 

 mla germanica the testes are func- 



Y """ 



m 



FIG. 459. Ovaries of Thysanura : A, of Cam- FIG. 460. Female genital organs of 



podea. , of Japyx. After Grassi. C, of Machilis. Lepinma saochtirina, adult: or, ovaries; 

 After Oudemans, from Sharp. a, part of the oviduct, corresponding to the 



calyx of winged insects; od, oviduct; rg, 

 vagina ; rx, copulatory pouch ; gg, accessory 



tinnnl fVivnnoTiniif lifp ftnr\ r>nnaicf frauds; m, muscles; n, nervous cord. 



te, ar SISt After Nassonow, from Peeler. 



of four lobes each. In the common 



cockroach (P. orientalis) (Fig. 461) the testes are functional only in 

 the young male ; they afterwards shrivel and are functionally replaced 

 by the vesiculae seminales and their appendages, when the later trans- 

 formations of the sperm-cells are effected. The accessory glands are 

 numerous and differ both in function and insertion. Two sets of 

 these glands (utriculi majores and breviores) are attached to the 

 vesiculae seminales and the fore end of the ejaculatory duct, while 

 another appendage, called by Miall and Denny the conglobate gland, 

 opens separately on the exterior upon a double hook, which forms a 



