CHONE FILICAUDATA. 297 
in front. It then diminishes gently to the tail, which is by no means acute. It is somewhat 
flattened and grooved anteriorly on the dorsum, and grooved ventrally from the ninth scute 
backward. A papilla marks the anus at the tip. The number of segments would appear 
to be about fifty, and they are distinctly marked, with the exception of the minute caudal 
rings. The anterior bristles (Plate CXXX, fig. 3) are in two groups—an upper with longer 
shafts and tapering winged tips, and a lower of spatulate forms (Plate CX XX, fig. 3a) with 
a short tapering process at the tip. The tufts are fewer and smaller than in C. Fawveli. 
Posteriorly in front of the tail the tips of the bristles are greatly elongated, and they slope 
forward rather than backward, projecting on each side as a fine fringe. 
The anterior hooks (Plate CX XX, fig. 36) are similar to those of Chone Fauveli, though 
smaller, the posterior part of the crown is less rounded, and the three or four teeth above it 
very sharp. The posterior hooks (Plate CX XX, fig. 3c), while generally resembling those 
of the common species, have somewhat higher crowns—five to six teeth being clearly 
visible above the main fang. The posterior part of the crown is also less rounded, as is the 
posterior outline. The main fang is proportionally shorter, since its point does not 
project beyond the line of the prow. Another feature is that the crown with its small teeth 
is on a level with the outer surface of the main fang, whereas in C. Fawveli the four large 
teeth above the main fang fit into a convex outline. The figure of Langerhans,’ though poor, 
clearly indicates the species. 
Reproduction.—Southern found a ripe male in August. 
The Chone longocirrata of Sars may be an allied form. Chamberlin? again makes a 
new species, Chone ungavana, of a form from Hudson Strait, King George’s Sound, and the 
posterior hooks certainly do not agree with those of C. Duneri or other species, though 
considerable variation occurs. 
3. CHONE FILICAUDATA, Southern, 1914. Plate CXXXI, figs. 1, 1’—1b—bristles and hooks. 
Specific Characters.—Cephalic region with a somewhat narrower collar than in C. Fawveli, 
entire ventrally, infolded dorsally. Lip-membrane terminates ventrally in a bifid process. 
Branchie eight to nine pairs, connected by a membrane almost to the tip of the filaments, 
which end in a bare subulate process. They are about half the length of the body. Body 
short and stout, 11 mm. long, about twenty-eight setigerous biannulate segments, of which 
eight are anterior and twenty posterior, the first and last achetous. It tapers toward the 
tail, which ends dorsally in a filiform cirrus or process. The dorsal longitudinal groove passes 
to the mid-ventral surface, and is continued from the first segment of the posterior region 
to the tail. Bristles of the anterior region of three kinds, viz., long slender forms with narrow 
striated wings, spatulate forms, and a series with delicately pointed tips and very narrow 
wings. All the shafts are longitudinally striated and dotted. Posterior bristles with attenuate 
tips and narrow wings. The anterior hooks have long, slightly curved shafts, very little 
dilated below the shoulder, with a main fang which leaves the neck at a little more than a 
right angle, and several teeth above it. A delicate wing occurs behind the crown (Southern), 
1 “Zeitschr. £. wiss. Zool., Bd. xxxiv, p. 114, Taf. vi, fig. 34. 
* “Canad. Arctic Exped. Polych.,’ p. 26, pl. vi. 
