128 



DISCOVERY REPORTS 



of the posterior lip of the chaeta sac disappears by the loth chaetiger. The gills begin 

 as a single filament on the loth-iith chaetiger (Fig. 46, b) and at the 20th are bifila- 

 mentous (Fig. 46, c). In the present specimens there are never more than two filaments. 

 The fully developed gill is two or three times as long as the dorsal cirrus. 



All the bristles of the first three modified chaetigers are broken off. The 4th foot 

 contains a dorsal bundle of capillary bristles (Fig. 46, d) and a ventral bundle of com- 

 pound bristles with knife-like blades (Fig. 46, e). There are three long pointed yellow 

 acicula supporting the feet. At the loth foot there are, in addition to the two types of 

 bristles already described, two or three dorsally situated comb chaetae (Fig. 46,/). At 

 about the 20th foot a pair of yellow hooded bidentate subacicular hooks (Fig. 46,^) 

 appear and take the place of the compound bristles. 



The dental formula is 7 — 9 : 9 + 6 — 6, and the details of the jaws are shown in the 

 figure (Fig. 46, h). The anterior part of the lower jaws (Fig. 46, /) is calcareous. 



Remarks. There are three known species of this rare abyssal genus, R. agassizi, 

 R. brevibrachiata and R. chuni. The present species is distinguished by the low number 

 of filaments to the gills and the character of its bristles. Fauvel apparently does not 

 accept the genus Rhomphobrachiiim , for he redescribes (1923, p. 417) the Diopafra 

 brevibrachiata, Ehlers (1875, p. 49), under the generic name Onuphis. Ehlers (1908, 

 p. 78) has himself recognised that this species falls within the genus Rhamphobrachium. 



Genus Onuphis, Audouin and Milne- Edwards 



Onuphis eremita, Audouin and Milne- Edwards. 



Fauvel, 1923, p. 414, fig. 163 a-l. 



St. 91. 8. ix. 26. -5 mile off Roman Rock, False Bay, South Africa. 35 m. GearNRL. Bottom: 

 sand. One specimen. 



Remarks. A single specimen incomplete posteriorly and 

 measuring 23 mm. by 2 mm. without the feet. There are 

 60 chaetigers. This specimen corresponds in detail with 

 Fauvel 's account. 



There are branchiae on every foot. Up to the 22nd foot 

 the branchiae are single: on the 23rd foot there are two 

 filaments, which are continued to the end of the fragment. 



That which Fauvel describes as a little conical tubercle 

 between the chaetigerous lobe and the base of the dorsal 

 cirrus is only present on the first three to four chaetigers. 

 It appears to be a prolongation of the anterior lip of the 

 chaeta sac. The ventral cirrus disappears by the 6th chaetiger -Lq 

 and the cirriform prolongation of the posterior lip of the Fig. 47. Onuphis eremita. 

 chaeta sac by the loth. ^""'^ '='^"'^'='- 



The dental formula is as follows: 7 — 8 : 8 + 6 — 8, I figure a comb chaeta (Fig. 47). 



