462 



ZOOLOGY 



SECT. 



The female reproductive organs consist of a pair of ovaries, a 

 pair of oviducts with a pair of receptacula ovorum, and two pairs of 

 receptacula seminis. The ovaries (ov) are minute pear-shaped bodies, 

 which are situated in the thirteenth segment, attached to the 

 septum between the twelfth and thirteenth. The oviducts (ov. d) 

 are a pair of short tubes, each with a comparatively wide funnel- 

 shaped opening into the cavity of the thirteenth segment, and 

 extending backwards and outwards in the fourteenth segment to 

 open at the female aperture on the ventral surface of the latter. 

 The receptacula ovorum are a pair of reniform sacs which open into 



cent, ves. sent ant. sp.res 



mid. ves se. 

 fiost. sp. res 



post, ves. sent- 

 vde/L. 



ov.d 



ov.cC 



Fio. 303. — ZiUmbricus herculeus. Reproductive organs, ant. sp. res. anterior sperm reser- 

 voir ; ant. ves. sent, anterior left vesicula seminalis ; fun, funnel-like openings of vasa efferentia; 

 int. intermuscular partitions ; mid. ves. sem. middle vesicula seminalis ; n. co. nerve-cord ; ov. 

 ovaries ; ov. d. oviducts ; post. sp. res. posterior sperm -reservoir ; post ves. stm. posterior 

 vesicula seminalis ; rec. receptacula seminis ; te, anterior, and te', posterior testes ; v. e'ff. 

 anterior, and v. eff'. posterior vas efferens ; v. def. vasa deferentia. (After Vogt and Jung.) 



The receptacula seminis 

 sacs which open on the exterior 

 ninth and tenth, and tenth and 



the funnel-shaped ends of t he oy iducts 

 (rec) are two pairs of rounTteasa 

 in the intervals between the 

 eleventh segments. 



Though hermaphrodite, the Earthworm is not self-impregnating , 

 but two individuals provide for mutual fertilisation by an act of 

 copulation. The copulating individuals apply themselves together 

 by their ventral surfaces, the heads pointing in opposite directions, 

 and become attached in this position by the setae of the genital 

 region and by a viscid secretion from the clitellum and of 



