286 EKUCHONE ROSEHA. 
he has not seen the interbranchial membrane. further investigations on this head are 
necessary, as both anterior and posterior hooks are in close resemblance. 
3. EUCHONE ROSEA, Langerhans, 1884. Plate CX XIX, figs. 8 and 8a—hooks. 
Specific Characters.—Cephalic collar wide, the anterior border being curved outward. 
Five pairs of branched cirri and several pairs unbranched, of which one long ventral 
pair is attached to the connecting membrane. Two eyes on the cephalic segment; two 
statocysts on the first bristled segment (Langerhans). (No eyes or otocysts, Southern). 
Body 4 mm. long, of a roseate colour; setigerous segments twenty, eight being anterior and 
twelve posterior. Anal scoop of four segments with an anterior median fold, and two 
lateral; pygidium with two eyes (Langerhans). Branchiz three to five on each side with a 
short, subulate process at the tip of the filament. The first setigerous segment has only 
dorsal capillary bristles, six long with conspicuous wings, the second row shorter, with curved 
tips and delicate wings. The other thoracic segments have tufts in which the upper are 
longer than the lower bristles, whilst inferiorly are spatulate forms. Below these are 
characteristic bristles with a double curvature and winged. The anterior crotchets have long 
shafts, a main tooth, four smaller teeth above it and a delicate wing. Posteriorly the 
bristles are long, slender and winged. Posterior hooks avicular, with a main fang, several 
teeth above it, and a narrow gulf beneath it. The anterior “‘ abdominal” hooks have fewer 
teeth above the main fang than the posterior, as Langerhans shows. 
SYNONYMS. 
1884. Huchone rosea, Langerhans. Zeitschr. f. wiss. Zool., Bd. xl, p. 271, Taf. xvi, figs. 35a—l. 
1914. $5 » Southern. Proc. Roy. Irish Acad., vol. xxxi, No. 47, p. 144, pl. xv, figs. 33 a—x. 
Habitat.—Ballynakill Harbour, 1—-3 fathoms (Southern). Abroad it occurs at Madeira 
on coral ground in deep water (Langerhans). 
The cephalic region bears a wide collar, the anterior border of which is curved outward, 
the dorsal margin infolded, but ventrally only slightly indented. The basal process for the 
branchiz bears two eyes in the examples from Madeira, none in the Irish. The terminal 
portions of the thoracic “* excretory organs” appear as dots under the collar. 
Three pairs of branchiz occur in those from Maderia, five pairs in the Irish, and Southern 
counted about twenty-six pinne on the filaments, which end in a bare subulate tip. 
Body of nearly uniform width, tapering, however, toward the tail, which has two eye- 
spots in the southern forms, none in the Irish. Ventrally are opaque-white glands or scutes, 
two on each segment in front, four posteriorly, since the ventral groove splits them. 
Two kinds of bristles appeared in the example kindly sent by Mr. Southern, viz., the 
longer dorsal with finely tapered tips and distinct wings, and the inferior with broader wings 
so as to render the tip slightly spatulate. Both are pale and translucent. Southern describes 
and figures (fig. 33F) a bristle with a narrowing of the shaft at the commencement of the 
wings, but he found none of the wingless capillary forms shown by Langerhans. The 
posterior bristles, as usual, have much more elongate, tapering winged tips. 
