A POLYNOID WITH BRANOHIiE. 433 



A Polynoid with Branchiae (Eupolyodontes 

 Cornishii). 



By 

 Florence Buchanan, B.Sc. 



With Plate 27. 



A SINGLE specimen of an interesting Polychsete was pre- 

 sented to the British Museum a short time ago by Mr. V. H. 

 Cornish, of the cable-ship " Mirror/' who had obtained it off 

 the mouth of the river Congo. It was shown to me by Professor 

 Bell, who n^as good enough to suggest that I should describe 

 it, and Dr. Giinther has kindly sanctioned my doing so. 



The worm is evidently a Polynoid belonging to the sub- 

 family Acoetidse. It is remarkably large even for that sub- 

 family, the specimen, although incomplete, measuring over a 

 foot in length, its breadth exceeding one and a half inches, 

 and its depth being nearly half an inch. It is, unfortunately, 

 somewhat mutilated, the alimentary canal being torn out, so 

 that the pharynx, which is a characteristic feature of the group, 

 cannot be diagnosed. The head and greater number of seg- 

 ments present are, however, complete externally, and while 

 showing clearly the genetic position of the worm, present also 

 characters of interest only slightly developed in other members 

 of the group, and which therefore have not hitherto received 

 sufficient attention. 



Before describing the worm itself I think it will be advisable 

 to review briefly the characteristics of the sub-family, and to 

 enumerate the few known species belonging to it, especially as 



