346 



THE EARTHWORM 



contains the ripe ova, arranged in a single row, each en- 

 closed in a vitelline 

 membrane and con- 

 taining a large nucleus 

 and nucleolus and a 

 number of granules of 

 food-yolk (p. 195). The 

 eggs are discharged 

 into the ccelome and 

 are received into the 

 female 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 septum and extending back into 

 the cavity of segment 14. 



15 



FIG. 86. Diagrammatic longitudinal section of 

 part of a Lumbricus, showing segments 

 9 15 and the contained generative organs 

 of one side 1X3. 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 indicated 

 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 ovi- 

 duct ; <J . aperture of spermiduct. The ovi- 

 duct, spermiduct, and seminal funnels are 

 indicated by thick lines. (From the Cambridge 

 Natural History, after Hesse.) 



