424 



ZOOLOGY 



SECT. 



cavity of the ninth segment, but extend into the tenth, where 

 they coalesce in the middle to form a large median sac of some- 

 what irregular form, the anterior sperm reservoir (ant. sp. res.). 

 The anterior pair of testes project into this, and the cells destined 

 to form the sperms, developed in the former, pass by dehiscence 

 into the large median cavity. On either side is a large ciliated 

 funnel, or rosette (fun.), leading outwards from the interior of the 

 reservoir. A second pair of vesiculae seminales (mid. ves. sera.), 

 situated in the eleventh segment, also open into the anterior 



a,nt. ves. sem 



ant. sprcs 

 int 



rec 



rec 



Tntd.ves se 

 post. ff>. r&s 



post, vas sen. 



vdefi. 



ct'.cL 



Fu;. 334. Iiumbricus agricola. Reproductive organs, ant. .<//. res. anterior sperm reservoir : 

 ant. ves. sem. anterior left vesicula seminalis \ fvn. funnel-like openings of vasa efferentia ; 

 int. interniuscular partitions ; mid. ves. sem. middle vesicula seminalis ; n. co. nerve cord ; or. 

 ovariss ; oc. (/.oviducts; post. ./. res. posterior sperm reservoir; post. n.<. ".m. posterior 

 vesicula seminalis ; rec. rcceptacula seminis ; te, anterior ; tc, posterior testes ; v. def. vasa 

 deferentia. (After Vogt and Jung.) 



sperm reservoir. A third pair (post. ves. sem.), situated in the 

 twelfth segment, unite in front to form the posterior sperm reservoir 

 (iwst. sp. res.), which lies in the middle of the cavity of the 

 eleventh segment. The posterior pairs of testes have the same 

 relation to this as the anterior pair have to the anterior reservoir ; 

 and a posterior pair of ciliated funnels (fun.) leads outwards from 

 its cavity. Each ciliated funnel leads to a narrow, somewhat con- 

 voluted duct, the i-((s cffercns, and the two vasa efferentia of each 

 side unite to form a ras defer ens or spcriniiluct (v. dcf.), right or 

 left as the ease in;i\ be. which passes almost straight backwards 



