HKUCHONE RUBROCINCTA. 283 
or six in front). Both have a rudimentary posterior basal process, a prominent prow, and 
the posterior outline is convex. Colour of the body pale reddish, anteriorly reddish-carmine. 
Branchize carmine with yellowish bands; cirri with whitish spots irregularly disposed ; 
tentacular filaments pale (Lo Bianco). 
SYNONYMS. 
1862. Chone rubrocincta, Sars. Forh. vid.-selsk., 1861, p. 128. 
UGB, og x idem. Indberet. acad. Colleg. Kongl, Fred.-Universit., p. 66. 
1874. Huchone rubrocincta, Malm. Annel. Géteb., p. 101. 
1883. a - Marion. Ann. Mus. Hist. Nat. Marseille, t.1, p. 26. 
1893. As ‘ Lo Bianco. Atti. R. Accad. Se. Nap., vol. v, No. 11, p. 78. 
1914. - P Southern. Proc. Roy. Irish Acad., vol. xxxi, No. 47, p. 144. 
1916. Pe me McIntosh. Ann. Nat. Hist., ser. 8, vol. xvi, p. 33. 
Habitat—Dredeed in 80—100 fathoms in St. Magnus Bay, Shetland, July, 1867 (J. G. 
Jeffreys), Ballynakill Harbour, 1—8 fathoms (Southern). 
Abroad it occurs in Norway. Sars found a species of Huchone at 300 fathoms, Skagerak ; 
Gulf of Marseilles (Marion). Mediterranean. at considerable depths (Lo Bianco). 
The collar dorsally has a curvature as it approaches the median fissure, whilst ventrally 
only a spout-like median fold occurs at the rim. The branchie are fifteen to sixteen on each 
side (12, Sars), connected by a web for half their leneth. The filaments have pinne which 
reach the base of the slender filiform tip (often so closely coiled as at first sight to represent a 
knob). A narrow hypodermic wing is attached to the axis along a considerable area of the 
pinnate region and to the base of the terminal process. ‘‘ Five pairs of branchial tentacles 
(tentacular cirri) and several unbranched, of which one long ventral pair is attached to the 
connecting membrane of the branchiz, whilst the others are free” (Southern). These organs 
are in close proximity to the mouth, have an afferent and efferent blood-vessel, and are 
probably of importance in alimentation. The course of the vessel is just within the hypo- 
dermic tip, which is slightly bulbous. 
The body reaches about three-quarters of an inch in spirit, has thirty-two or 
more segments, of which nine to eleven are included in the anal funnel, which has a 
furrowed process in front and a crenulated margin. It is somewhat rounded, though the 
ventral surface is more or less flattened, a little tapered in front, and more distinctly diminished 
in the caudal region. The segments are two-ringed, and a dorsal furrow runs from end to 
end, for it does not cease when the ordinary groove bends to the right as it passes to the ventral 
surface between the eighth and ninth segments, and is continued to the anal funnel. The 
anterior scutes are divided by the transverse furrow of the segment; the posterior scutes 
are cut into four by the deep and broad ventral groove. 
The anterior bristles are borne on setigerous processes, and are pale and brittle. The first 
tuft, which arises a little more dorsal than the others and at the base of the collar, consists 
of a longer and shorter series of finely tapered bristles with very narrow wings, those on the 
shorter series being almost invisible. The average anterior tuft presents three sets of bristles, 
the longer (Plate CX X XI, fig. 2) having straight shafts and gently tapered and slightly curved 
tips; the next series (Plate CXXXI, fig 2’) has shorter tips with a distinct inclination back- 
ward, and broader wings, but still their condition is in contrast with the broad spatulate 
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