192 AET. II. A. IZUKA : 



maining segments provided with uniramous or biramous parapodia ; 

 dorsal ramus generally reduced, furnished with simple bristles ; 

 ventral ramus with compound bristles. Dorsal and ventral cirri 

 fihform, faintly annulated. 



Genus Hesione Savigny. 



Prostomium small, distinct, with 4 eyes and 2 tentacles. 

 Tentacular cirri 16. Proboscis protrusible and unarmed. Body 

 consisting of a small number of segments. Parapodium uni- 

 ramous, with compound bristles. 



Hesione reticulata Marenz. 



PL IL, fig. 7. 



1879. Hesione reticulata, Marenzeller. Südjap. AniieL, p. 21, Taf. Ill, 

 Fig. 4. 



Body consists of 19 segments, of which 16 are setigerous. 

 Length of a medium sized specimen, 58 mm. ; maximum breadth 

 in 11th segment, 9 mm. without and 16 mm. with parapodia and 

 bristles. Length of the largest specimen ever got in Japan 

 90 mm. ; breadth 10 mm. and 18 mm. respectively. 



Dorsal surface greatly arched. The cushion-like side-region 

 occupies about J of the lateral half of segment at about the 10th 

 segment. 



Dorsum brownish red with light greenish iridescence ; pro- 

 stomium and anterior few segments deeper in colour, gradually 

 fading towards posterior segments. At about the middle of 

 each segment, there are observed three white spots situated in a 

 transverse line ; these white spots are continuous in the 2nd, 



