148 AET. II. — A. IZÜKA : 



paragnathi either on both rings or on maxillary ring alone, rarely 

 entirely absent or coexistent with soft papillae. 



Epiiocous phase : — Generally both the rami and cirri of para- 

 podia peculiarly enlarged ; eyes larger, and inter- segmental annuli 

 more distinct, than in the atocous phase. Bristles on parapodia 

 partly or entirely replaced by paddle- shaped ones. 



The method followed below in describing the proboscis and 

 paragnathi of the various species is that of Kinbeeg, — a method 

 which has been adopted also by Geube, Clapaeède, Ehlees and 

 MgIntosh. Thus, the distal region of protruded proboscis is called 

 the maxillary ring, and the proximal the basal ring. Of the several 

 series of paragnathi, the median dorsal series at base of maxillae 

 is called the first (I.) ; the group on each side of the foregoing 

 is called the second (IL) ; the median ventral group at base of 

 maxillae, the third (III.) ; the lateral series adjoining the last, the 

 fourth (IV.) ; the median dorsal series on the basal ring of proboscis, 

 the fifth (Y.) ; the lateral series on each side of the foregoing, 

 the sixth (VI.) ; the remaining ventral and lateral paragnathi 

 of the same ring, generally disposed in a more or less continuous 

 series, form the seventh and eighth series (VII. and VIII.). 



Nereis 'inictodonta Marenzeller. 



PI. XVI, figs. 1—6. 

 1879. Kereis mictodonta, Marenzeller. SiidjaxD. AnneL, p. 10, Taf. IT, 



rig. 2. 



This is one of the commonest marine annelids found between 

 tide-marks in Japan. Its distribution ranges from Benin Islands 

 in the south to the Bay of Matsushima in the north. 



