8 CALIFORNIA ACADEMY OF SCIENCES. 



Pl.ATB II. 



Fij^. 8. Ventral nerve trunk and cephalic ganglion. 

 I""ig. 9. Seminal receptacles and allnuiiinous gland. 



re. seni.: seiniiuil receptacles. 



gl. alb.: albuminous gland. 

 Fig. 10. Interior extremity of one of the receptacles, showing the sperma- 

 tozoa accumulat('(l in the same. 



Fig. 11. One of the oviduct.-^, with eggs in the act of descending. 

 Fig. 12. The interioj- extremity of one of the segmental organs. 

 Fig. 13. One pair of spines. 

 Fig. 14. Interior view of the ventral part of the worm. 



gl. alb.: albuminous gland. 



re. sem.: seminal recoptarles. 



test. : testes. 



ov. : ovaries. 



ovd.: oviducts. 



utr. : atrium. 



efT. d.: ell'iTi'iit ducts. 



Fig. 15. One of the egg capsules or cocoons. In the interior are seen three 

 young worms, magnified about live times. 



The Roman numerals everywhere indicate the segments. In numbering the 

 same 1 have everywhere in this pnp(M' referred to the first segment as segment 

 I, thus following Vejdovsky and others. In former papers 1 have always referred 

 to the (iist setigerous segment as segment 1, anil believe yet this way to be the least 

 confusing. Hut as uniformity in numerating • the segments is highly desirable, 

 and as every investigator seems to have his pet way, leading to endless misunder- 

 standing, I shall for the future accept the system used in this paper, hoi)ing all 

 other- investigators will do the same. 



