346 



THE EARTHWORM 



CHAP. 



sg.s 



distal end contains the ripe ova, arranged in a single row, 



each enclosed in a 

 vitelline membrane and 

 containing a large nu- 

 cleus and nucleolus 

 and a number of 

 granules of food-yolk 

 (p. 195). The eggs 

 are discharged into 

 the ccelome and are 

 received into the fe- 

 male gonoducts or 

 oviducts (Fig. 82, o. d, 

 and Fig. 86) two 

 short tubes, each with 

 a wide ciliated mouth, 

 placed opposite the 

 corresponding ovary. 

 The oviduct perforates 

 the next following sep- 

 tum (i.e., that between 

 segments thirteen and 

 fourteen) to open by 

 a minute aperture on 

 the fourteenth seg- 

 ment, near the ventral 

 couple of setae. Con- 

 nected with the mouth 

 of each oviduct is 

 a small egg-sac (Fig. 

 82, r. o, Fig. 86, e. s), 

 developed as an out- 

 growth from the same 

 into the cavity of seg- 



fc- 



15 



I'iG. 86. Diagrammatic longitudinal section of 

 part of a Lumbricus, showing segments 

 9-15 and the contained generative organs 

 of one side : X 7. In the body-wall the cuticle 

 is indicated by a clear space, the circular 

 muscles by irregular dots, the longitudinal 

 muscles by dotted longitudinal lines, and the 

 peritoneal membrane by a thin line. 



e. s. egg-sac ; o. ovary ; sp. aperture of anterior 

 spermotheca both spermothecae are indi- 

 cated by dotted lines ; sp. s. posterior sperm- 

 sac, the anterior and middle sacs .are not 

 lettered ; ss. sperm-reservoir ; t. anterior 

 spermary the posterior is not lettered ; 

 $. aperture of oviduct; <J> aperture of 

 spermiduct. The oviduct, spermiduct, and 

 seminal funnels are indicated by thick lines. 

 (From the Cambridge Natural History, 

 after Hesse.) 



septum and extending back 

 ment fourteen. 



