452 MARPHYSA KINBERGt. 



teeth. Mandible with the oblique anterior edge smooth, the outer angle, however, being 

 prominent. The branchise form an isolated tuft, commencing about the sixteenth 

 and continuing to the thirty-sixth foot. The anterior gills have from five to nine 

 filaments, those best developed twenty-four or twenty-five. The foot has a short subu- 

 late dorsal cirrus in front, but it becomes longer in its progress backward. The setigerous 

 region bears longer dorsal bristles than in Marphysa Belli, and brush-shaped forms, whilst 

 the inferior group is composed only of those with long tapering tips, as in Marphysa 

 sanguinea. Posteriorly the dorsal bristles are longer, and the long bifid brown ventral 

 hook projects inferiorly. 



Habitat. — Dredged in the ' Porcupine ' Expedition of 1870 nine miles off Cape Finis - 

 terre in eighty-one fathoms on a hard bottom with sandy mud. Though not procured in 

 what are usually considered British waters, it has been thought proper to include this 

 species here. 



Proboscis. — The maxillse are pale chocolate brown with darker blades which do not 

 rise much above the horizontal. They are articulated posteriorly to two rather long 

 lobate processes which are somewhat narrowed at the commencement. The great dental 

 plates have six teeth, the anterior being long and recurved, and a considerable posterior 

 region being smooth. The azygos plate on the left has about seven teeth. The anterior 

 plate on the right has six teeth ; that on the left has fewer. A dark horny patch also 

 occurs in front on each side. The mandibles have the oblique anterior edge smooth, the 

 outer angle, however, being prominent. 



The branchias commence on the sixteenth foot, thus differing from Marphysa Belli 

 from the Channel Islands. The initial filament occurs only on one side (the right). The 

 seventeenth on. the right has a considerable gill of nine filaments ; that on the left five or 

 six. They are present in all on twenty segments, the last having fewer filaments. The 

 whole forms a somewhat isolated and dense tuft, some of the best developed (Plate 

 LXXIV, fig. 9 a) having twenty-four or twenty-five filaments which are longest in the 

 middle, and arise as usual from the side of the branchial stem. 



At the tenth foot (Plate LXXIV, fig. 9) the dorsal cirrus is a proportionally large 

 subulate process — somewhat constricted at the base. The setigerous region has a bluntly 

 conical outline, with a conical lamella projecting beyond it. It is supported by three 

 black spines. Dorsally it bears a dense group of translucent simple bristles, the tips of 

 which have a very slight expansion and then taper to a fine point (Plate LXXXIII, 

 fig. 6). Ventrally are the even more numerous jointed bristles (Plate LXXXIII, fig. 

 6 a), which have translucent shafts with dilated distal ends showing fine striaa, and 

 serrations on the edge. The terminal piece forms a long tapering spear which diminishes 

 m length from the upper bristles downward. Moreover, when fracture occurs near the 

 attachment of the distal piece a portion remains at the socket, a condition not usually 

 seen in such forms, and indicating a differentiation of the point of attachment (Plate 

 LXXXIII, fig. 6 b). Each foot has a rete mirabile of branching blood-vessels. 



The closeness in external resemblance between this species and M. Belli, Aud. 

 and Edw., is interesting — associated as it is with the divergent structure of the 

 bristles. 



