418 HYALINCECIA SICULA. 



prominent processes being guarded by wings. The simple bristles have very narrow 

 wings. The powerful posterior hooks somewhat resemble the bifid forms of Eunice and 

 of other Oiruphids. The tube is long and narrow, formed of an inner lining of secretion, 

 more or less strengthened by minute particles of shells, fragments of echinoderms, and 

 similar structures. 



Synonyms. 



1865. Onuphis sicula, De Quatrefages. Annel., p. 352. 



!869. „ „ Mcintosh. Rep. Brit. Assoc. (1868), p. 337. 



„ Hyalinoecia sicula, idem. Trans. Roy. Soc. Edinb., vol. xxv, p. 418, pi. xvi ; f. 3, 36, 3c. 

 1870. „ bilineata, Baird. Journ. Linn. Soc, vol. x, p. 358. 



1901. Onuphis sicula, Whiteaves. Geol. Sarv. Canada, No. 722, p. 80. 

 1903. „ „ Mcintosh. Ann. Nat. Hist., ser. 7, vol. xi, p. 557. 



Habitat— In ninety fathoms off North Unst, Shetland (J. G. Jeffreys) ; Plymouth 

 (Allen); Coast of Cornwall (Baird); Connemara, Galway (A. G. Moore). ' Porcupine ' 

 Expedition of 1869, off the coast of Ireland in sticky mud at 370 fathoms; Nymph Bank, 

 S.W. Ireland, in 52J fathoms, Eoyal Irish Academy's Expedition, 1886. 'Porcupine' 

 Expedition of 1870, at Station VIII, Lat. 48° 26' N., Long. 9° 44' W., in 358 fathoms and 

 a bottom temperature of 50° F., and at various stations in the southern waters without 

 and within the Mediterranean, generally on sand or muddy sand. Also obtained by the 

 ' Knight Errant ' at Station III. 



Shores of Italy, Sicily, and Palermo (De Quatrefages). 'Porcupine' Expedition, 

 1870, east of Cape de Gatte, six miles from shore in 60 — 160 fathoms. Gulf of St. 

 Lawrence (collected by Whiteaves). 



Head (Plate LXIV, fig. 4) with three elongated tentacles — a median and two lateral 

 as in Hyalinoecia hibicola. The small black eyes lie to the exterior of the base of the long 

 lateral. All the tentacles have ringed bases, and in the preparations (spirit) they often 

 present crenations or pseudo-articulations. 



Body characterized in spirit by two parallel bands of brown which course along the 

 iridescent dorsum from a transverse belt of the same colour immediately behind the head, 

 and by a brown spot between each foot from the fifth backward. 



Proboscis. — Maxillae (Plate LXIV, fig. 4 a) strongly curved and sharp-pointed. The 

 posterior appendages are elongated and conical. The right great dental plate has nine or 

 ten teeth. The left great dental plate has eight teeth; the azygos plate has eight. The 

 curved anterior plates seem to have few teeth, four or five on the right, fewer on the left, 

 but they may have been broken. The mandibles (Plate LXIV, fig. 4 b) have long, narrow, 

 slightly curved and tapering shafts, and a blunt leaf-like anterior region with a few 

 notches. The branchiae commence as a simple filament on the dorsal cirrus of the fifth 

 foot, and appear to extend far backward (beyond the fiftieth foot), but both they and the 

 cirrus are considerably diminished in size, the branchia, at first the smaller, becoming the 

 larger and continuing so to the end of the fragments. 



In the structure of the bristles of the anterior feet a marked difference distinguishes 

 this species from Hyalinoecia tubicola and 0. coiichylega, since instead of the large un- 

 jointed winged hooks characteristic of these, jointed or compound forms, after the fashion 



