REPRODUCTIVE SYSTEM OF EARTHWORM 



253 



lumen is a portion of the body cavity. This is of import- 

 ance, for in Polychaetes the genital products mature in the 

 general body cavity, just as the spermatozoa in the earth- 

 worm mature in the seminal vesicles. 



(3) From the seminal vesicles the spermatozoa are carried 

 to the exterior by means of the vasa deferentia. The in- 

 ternal openings of these are large and funnel-shaped, and 

 are concealed by the seminal vesicles. Each of the four 



0Vd4 



Fig. 136. — Reproductive organs of earthworm. - 



After Hering. 



N., Nerve-cord ; T., anterior testes ; S., sacs of setse ; R.S., 

 receptacula seminis ; s.f., seminal funnels ; v.d., vas deferens ; 

 ovd., oviduct ; ov., ovary ; s.v., seminal vesicles cut open ; 

 VIII.'XV., segments. 



funnels opens into a duct, and the two ducts unite at each 

 side to form the two elongated vasa deferentia, which pass 

 backwards to open externally on the 15th segment. 



(b) The Female Organs consist of two ovaries and two 

 oviducts, each of which has a side receptacle for the eggs. 



(i) The two ovaries are small bodies situated near the 

 nerve-cord on the septum between segments 12-13. Each 

 is pear-shaped, the stalk of the pear being a string of ripe 

 ova. They are more readily seen than the testes. 



