Benham. — Earthivorms from the Eermadecs. 299 



of c and d descend slightly, so that the gap be is reduced, and dd 

 increased, in the forepart of the body. 



Prostomium epilobic, about one-half, without a posterior 

 transverse groove. 



Clitellum covers segments 13-18 inclusive. The ventral 

 chaetae and intersegmental furrows are visible, though the skin 

 is somewhat thickened across the ventral surface. 



Genital Pores, &c. — A pair of large porophores on the 17th 

 segment, in line with chaetae ab ; and in front of the chaetae there 

 is a single large median " copulatory tubercle," in the form of 

 an oval glandular pad, not very prominent, covering the whole 

 of the ventral surface of segment 19, and the prechaetal region 

 of the 20th. 



Dorsal pores are visible posteriorly. 



Internal Anatomy. — In the bisected individual I made out 

 the following points, sufficient to characterize the species : 

 The dorsal blood-vessel is enlarged in segments 14, 15, and 16 ; 

 the last hearts are in the 13th segment. The gizzard is quite 

 minute, in segment 5. There is no oesophageal gland, though 

 the tube is dilated in the 13th and 14th segments. The intestine 

 commences in the 18th. 



The Reproductive System. — The sperm-sacs lie in segments 

 9, 11, and 12. The prostate is a large, tongue-shaped gland, 

 extending through the six segments 17-22, with a short muscular 

 duct in the 17th. A couple of long chaetal sacs underlie the 

 prostate, extending back from the 17th to the 21st segment. 

 Each sac contains three chaetae — a functional " penial chaeta " 

 and two smaller ones at different stages of development. The 

 penial chaeta (Plate XIV., figs. 4, 5) is long, delicate, and bent 

 distally. The tip is curved, spoon-shaped, so that the side and 

 top views differ. The surface is quite devoid of ornamentation. 



There are three pairs of spermathecae, in the segments 7, 8, 

 and 9. Each (Plate XIV., fig. 1) is an ovoid sac, with a 

 short muscular duct about half the diameter of the sac. It 

 receives close to the body-wall a long cylindrical diverticulum, 

 which in the specimen studied is curved in an S-shaped manner. 

 The tip is not dilated (till compressed), but the base is enlarged 

 at its union with the duct. 



Remarks. — In the possession of three pairs of spermathecae 

 tms species resembles R. cockayni from Campbell Island, from 

 which, however, it differs in its colour, dimensions, arrangement 

 of copulatory tubercle, and form of penial chaeta. 



