36 NEPHTHYS CIRROSA. 



Loxosomas occur on the feet of those from St. Magnus Bay, Shetland. 



It is possible, as Ehlers thought, that Dr. Johnston's K longisetosa refers to this 

 species. He considered that it approached K Hombergii (Aud. and Ed.), though 

 differing from it, and he courteously named it after the British author. 



(Ersted's Nephthys longisetosa (1843) makes so close an approach to this species that 

 it may be included under it. 



8. Nephthys cierosa, Ehlers, 1868. Plate LVII, figs. 17 and 18; Plate LXVII, fig. 3 

 —foot; Plate LXXVI, figs. 12 and 13— bristles. 



Specific Characters. — Head longer than broad, seven-sided, with a pair of conical 

 tentacles in front, and a longer pair, latero-ventrally situated, considerably behind, A 

 small (nuchal) papilla on each side posteriorly. The translucent area to the inner side of 

 the anterior tentacles is distinct in some examples. Mouth a triradiate slit, for a fissure 

 runs forward between the anterior flaps. Proboscis of the normal shape, with twenty- 

 two rows of rather long papilla anteriorly in extrusion — each row having six or more 

 papillae, which diminish in length proximally. Shorter papillee occur over the general 

 surface of the organ. A single dorsal median cirrus is present, as in N. ciliata, only it 

 is slender. The terminal arches of bifid papilla? are normal. The first foot has two 

 bristle-tufts and a comparatively large ventral cirrus. Eoot with an arched dorsal 

 lamella of considerable breadth, highest in the middle. No other flap. Dorsal cirrus 

 of average length, subulate and rather slender. Branchia of moderate size, slightly 

 coiled outward. The ventral division has a posterior lamella of moderate size, directed 

 upward, and with a small flap superiorly over the base of the bristles. The ventral 

 cirrus is prominent and somewhat conical. Bristles rather long and curved, pale golden; 

 longer forms show a marked curve of the blade and a finely serrated edge. Barred 

 forms with a spindle-shaped "camerated" region. Moreover, a little modification of 

 the parts of the foot brings it close to N. hystricis, which, however, may readily be 

 distinguished by the longer bristles, the larger spinigerous lobe, the smaller lamella? 

 superiorly and inferiorly, and the free flaps from the fillet guarding the barred bristles 

 in both divisions of the foot. 



Synonyms. 



1868. Nephthys cirrosa, Ehlers. Die Borst. ii, p. 624, Taf . xxiii, figs. 6, 38, and 39. 

 1883. „ cseca, When. Clmetop. 'Vega' Exped., p. 392. 



1890. „ „ Malaquin. Annel. Polycli. Boul., p. 33. 



1894. „ „ De Saint-Joseph. Annel. Pol. Dinard, Ann. Sc. Nat., 8th ser., xyii, p. 20, pi 



fig. 19. 



1900. „ „ Mcintosh. Ann. Nat. Hist., ser. 7, vol. v, p. 261. 



1901. „ „ idem. Ibid, vol. viii, p. 222. 



1904. 



Allen. Journ M.B.A., n.s., vol. vii, p. 225. 



