136 MR. CYRIL CROSSLAND ON THE [Juiie 16, 



intelligible descriptions have been j)iiblislied, may be useful to 

 futui'e woi-kei^s : — 



A, Prostomium undivided. 



1. Gills large, confined to a few anterior segments *. 



M. stragultmi, 31. belli, 31. adenensis. 



2. Gills of moderate size, extending over most of the 



body's length 31. macintoslii, sp. nov. 



B. Prostomium bifid. 



a. Capillar}' setaj onlj' present 31. mossamhica . 



j3. Tentacles three times length of the prostomium. 



1. Compound setiB hooked 31. goodsiri. 



2. Compound setae vritli knife-like articulated 



pieces 31. acicularii'm. 



y. Tentacles not twice length of prostomium. 



1. Gills of one or two filaments only : 



Compound seta? of both kinds If.fallax. 



„ „ with hooked aiDpendage ... 3£. sa.vicola. 



„ „ „ knife-like appendage 



onlj' 3£. striata. 



2. Gills of moderate size : . j^j- \.^y„iiina 



a. With hooked compound seta3 in/., l7,-„ 



rt 1 -j; Ti J *. C ill". siMpZea*, sp. nov. 



/3. „ knife-hke compound setcC | M.furcelldta, sp. nov. 



Grube (" Mittlieilungen liber die Familie der Euniceen " Katur- 

 wiss. Sciiles. Ges. 1877) gives numerous species of this genus 

 from Schmarda, who, however, described them under the name 

 Uunice, in the definition of which genus he said that tentacular 

 cirri may be present or absent. In only one case, that of Eunice 

 teretiitscula, is it definitely stated that they are absent, though 

 they are not mentioned in the three other species which Grube 

 entimerates. But four species of Mmyhysa and five of Eunice 

 in one collection is so disproportionate that I am inclined to 

 think that M. teretiuscula is the oixly true Marphysa here. In 

 any case Schmarda's descriptions are so shoi-t and his figures so 

 rough that in most instances it is not possible to compare them 

 with others with any certainty. It is quite possible indeed that 

 my species M. simplex is the above-mentioned E. teretiuscida, 

 both being from the Indian Ocean, but as certainty is not possible 

 I have redescribed my species de novo. 



The following references give the best available descriptions 

 (mere notes are not inserted here unless important) : — 



M. stracjulum Y. Grube. ' Annulata Semperiana,' p. 163. 



M. belli Ehlers. ' American Annelids ' (U.S. Fishery Survey by 

 the 'Blake'). 1887. 



M. adenensis Gravier. " Polychetes de la Mer Eouge," Arch. 

 I^ouv. du Museum de Paris, 1900. 



M. mossambica {M. novce.-Jwllandice) Grube. ' Annulata Sempe- 

 riana.' Gravier, loc. cit. 



M. goodsiri Ihtt^i ,^i,, ,^ 



M. bonhardi \ ^^I^^^osh. ' Challenger' Reports, vol. xii. p. 299. 



* 3Iacdi(.ffia honliardi (Mcintosh, ' Challenger ' Eeports, vol. xii.) should be 

 mserted here. Its main characteristic is the possession of four pairs only of well- 

 developed gills. 



