28 



LUMBRICUS 



6. Nervous system, genitalia, and nephridia, as exposed when the alimentary canal, together with supra- 

 and sub-intestinal blood-vessels, has been reflected forward as in 5 : supra-pharyngeal ganglia (segment 3) ; 

 circum-pharyngeal commissure ; sub-pharyngeal ganglia (segment 4) ; ventral nerve cord ; spermathecce ; nephridia ; 

 anterior vesicula seminalis (segment 10) ; posterior vesicula seminalis (segment n) ; ovaries (segment 13). 



