174 ART. II. — A. IZUKA : 



arranged larger, and of several posterior rows of densely arranged 

 smaller, ones. 



Maxillae strong, with 8 teeth. 



Epitocous phase : — The anterior 29 parapodia unchanged ; in 

 the 3 0th the change is slight, bat after that it soon reaches 

 maximum degree. Dorsal region of superior ligula becomes thin 

 and broad ; ventral border of dorsal cirrus shows a serrated or 

 warty appearance ; ventral lobe of dorsal ramus and pre-setal 

 lobe of ventral ramus are greatly enlarged, the former becoming 

 oblong and the latter oval in shape ; basal region of ventral 

 cirrus develops into thin wing-like flap. The ordinary bristles are 

 replaced by paddle -shaped ones. 



Habitat : — AVakkanai in Prov. Kitami (Mr. H. Watanabe) ; 

 Oshoro in Prov. Shiribeshi ; Mororan Harbour in Prov. Iburi (!) ; 

 Shimushu, June 25th, 1903 (Mr. K. Yendo). 



Wereis ijiinal n. sp. 



PI. II, fig. 1 ; Pi. XIX, figs. 1—9. 



This gigantic Nereid reaches 390 mm. in length, consisting 

 of 215 segments ; the breadth increases from the first segment, 

 which is G mm., to about the 60th, where it measures 12 mm., or 

 20 mm. including parapodia and bristles. After that the body 

 tapers gradually toward the posterior end. 



The dorsum in the anterior reigion is of a light l^rownish 

 colour, which passes posteriorly, in the main parts of body, 

 into a deep brownish with slightly metallic iridescence. This 

 again gi-adually becomes lighter toward the posterior end of body, 

 which is almost of a flesh colour. The ventral surface as well 



