VI 



.1 RA CHNOIDEA —SEXUAL ORGANS 



535 



vesicles ; if there are 4 they lie in the course of the 4 speiin ducts, if 2 in the course 

 of the 2 common efferent ducts. 



Pedipalpi. — The ovaries and testes are paired with paired ducts, and a common 

 unpaired genital aperture on the ventral side of the first abdominal segment. The 

 Phrynida- are viviparous. 



Microthelyphonidse. — The germ glands (the ovaries at least) are said to be un- 

 paired. There are probably 2 oviducts, which open outward by means of a common 

 terminal piece on the venti'al side of the first abdominal segment. 



Araneidae. Female Apparatus (Fig. 375, D). — There are in the abdomen 2 wide 

 tubes, beset with numerous ovarian follicles, and looking like a cluster of grapes. 

 The free ends of the ovaries sometimes fuse in such a way as to give rise to an un- 

 paired circular ovary. There are always two short oviducts, uniting to form a short 

 terminal portion (vagina), which emerges through the unpaired median genital 

 aperture at the base of the abdomen, on the ventral side, between or somewhat 

 behind the anterior pair of stigmata. All female Araneidce possess receptacula 

 seminis. There is either one receptaculum, or two lateral receptacula, less frequently 

 three, one median and two lateral. These receptacula, into which, during copula- 

 tion, the semen is introduced, are entirely separate from the sexual apparatus in 

 many Araneidce, and have separate outer apertures near the female genital apertures. 

 In others they are accessory organs of the vagina. In Epeira each of the two 

 receptacula has 2 apertures — an outer one, placed on the genital plate near the 

 sexual aperture, and an inner one leading into the vagina. 



Male Apparatus (Fig. 376, D). — Two testes lie as long tubes in the abdomen, and 

 are continued as 2 long thin and often much coiled sperm ducts, these opening out- 

 ward by means of a short wide common duct through the male genital aperture, which 

 lies between the 2 anterior stigmata. The transition from the testes into the vasa 

 deferentia is often gradual, so that it is difficult to say where the former leave off and 

 the latter begin. Occasionally the blind ends of the 2 testes are imited by connec- 

 tive tissue. 



In the male sexual apparatus of the Araneidce a special copulatory organ is 

 wanting. The pedipalps of the male function as copulatory organs, their terminal 

 joints (Fig. 377) being transformed in a 

 peculiar manner. The inner side of this 

 terminal joint carries an outgrowth, through 

 which runs a spirally coiled canal emerging 

 at the pointed end. This canal is filled by 

 the male with sperm from the genital aper- 

 ture. "When copulation takes place the 

 point of the outgrowth of the pedipalp is 

 introduced into the receptaculum seminis of 

 the female, and the semen discharged from 

 the spiral canal into the receptaculum. 



Phalangldse (Fig. 375, F, Fig. 376, S). 

 — Both the ovaries and testes are here un- 

 paired. Each germ gland is a semicircular tube which, by analogy with the 

 arrangement described in the Araneidce, may well be considered to have arisen by the 

 fusing of the blind ends of originally paired germ glands. The ovarian tube is 

 superficially beset with ovarian follicles. The 2 ends of the germ glands are con- 

 tinued into 2 ducts (sperm ducts in the male, oviducts in the female), and^ these 

 unite to form a common duct which enters the coijulatory apparatus. This, in the 

 male, is a rod-like penis, in the female, a long cylindrical ovipositor. Both the penis 

 and the ovipositor are enclosed in special sheaths, and they can, together with their 

 sheaths, be protraded and evaginated. The 2 vasa deferentia are very much coiled 



Fig. 877.— Last joint of tlie padlpalp of Fill- 

 stata testacea Latr. (after Bertkau). 



