EKKANTIAÏE POLYCHAETA OF JAPAN. 131 



Habitat, — Suruga Bay, G 5 fathoms ("Albatross"); Saganii 

 Bay, 42 fathoms (" Golden lîmd "). 



Genus 3Iarphysa Qiiatrefages. 



Prostomium with 5 posterior tentacles ; anterioi' short 

 tentacles absent as in Eunice. Eyes situated externally to inner 

 lateral tentacles. Tentacular cirri absent. Anal cirri 4. Bran- 

 chiae semi-pectinate or simple. Maxillary apparatus as in Eunice. 



Marphysa iivainusi n. sp. 



PL I, fig. 8 ; PI. XIV, figs. 11—16. 



This is one of the most common littoral annelids in Japan. 



The body measures 300-350 mm. in length, and 9-10 mm. 

 in breadth in the widest parts at about 25th segment ; tapering 

 toward both ends. Segments up to 340 in number. 



The anteriormost few segments are nearly circular in cross- 

 section ; posteriorly the segments become gradually llattened and 

 wider, attaining: maximum breadth at about 25tli seirment ; thence 

 toward the posterior extremity the breadth again very gradually 

 reduces itself. 



The colour of the living animal is dorsally uniformly reddish- 

 brown, except the anteriormost parts, together with the head, 

 wliicb WW of ;i, reddish-purple brown colour with metallic 

 iridescence. Tlie ventral surface is usually of a lighter reddish 

 ln'owii eoloiir (hail the dorsum. 



Prostomiiiin la r^e, twice as broad as longr and 2-lobed, anteriorly 

 indented l)y a (lee|) uotdi ; a median groove extends from this 

 in itch posterioil\' ainiosl (o base of the median tentacle. Ten- 



