300 CHONE REAYI. 
The cephalic plate has a thinner but fuller collar than in Chone Fauveli, and its edges 
are turned in dorsally, sloped inward and backward, to be fixed to the first segment on each 
side of the middle line and to the sides of the groove in front, but its anterior margin is well 
behind the free edge of the collar above, and no continuation of this part occurs in front— 
a distinctive feature with such as Chone Duneri and others. As in the former species and in 
C. Princet, the fissure presents a pouch at the attachment of the collar posteriorly. The 
collar passes with a slightly crenate margin nearly straight to the ventral surface, but, from 
attachment, the free rim is there narrow. In this species the bases to which the branchie 
are attached are different (Plate CX XXI, figs. le and 1f), for they form two semicircular, 
soft grooved lobes which do not project beyond the margin of the collar im lateral view. 
To the inner (median) or straight edges the cirri are attached, and the whole base is con- 
stricted posteriorly, so that it 1s mushroom-like. There is no bifid process of the lip- 
membrane as described by Southern in Chone filicaudata. 
Each branchial filament has a large camerated, chordoid axis, which extends into the 
elongated terminal process as a fine thread. The long pinne arise in a double row and continue 
to the base of the terminal process, the sides of which have a series of short pine, giving a 
character to the organ, and which gradually diminish, leaving a smooth, subulate process 
(Plate CX XX, fig. 5), much shorter than in Chone Duneri and of a different character. As 
a transparent object, the filament shows a series of rounded areas inside the chordoid axis, 
which probably represent the bases of the pimne. Few species show the structure of these 
organs more clearly. 
The body is shorter and smaller than in C. Fawvel, the largest example being fully an 
inch in spirit, and having about fifty-five segments, of which eight bristled are anterior. It is 
rounded throughout the greater part of its extent, especially dorsally, and only at the posterior 
third is the ventral surface flattened as it tapers to the tail, the tip of which projects as a 
special process with an oblique end—the slope of the anus being from above downward and 
forward. A little pigment occurs dorsally and ventrally at the tip, which in a small example 
had a minute filiform process, so that C. filicaudata is not the only form so provided. From 
the dorsal fissure at the collar a groove runs backward in the middle line to the end of the 
seventh bristled segment, then slants to the right across the eighth dorsally and the ninth 
ventrally to the middle line at its posterior border, and thence backward to the tip of the 
tail. The segments show a few transverse lines, but only a few of the anterior ventrally are 
distinctly divided into two rings. The anterior region has eight bristle-tufts and seven 
uncinigerous rows. 
The first bristle-tuft consists of simple bristles, but the second and those following in 
the anterior region are of two kinds, viz., a dorsal series of translucent bristles, with a pale 
golden sheen when viewed under a lens, and long tapering tips, with very narrow wings 
(Plate CXXX, fig. 1), which disappear before reaching the extremity, and of a spatulate 
ventral series (Plate CX XX, figs. la and 1b), with cylindrical shafts, the tips of which project 
a little beyond the surface, and end in a delicate filament. The wings are at first narrow, 
expand into a spatulateregion, then gradually cease as a narrowrim on the base of the terminal 
filament. The prolongation at the tip distinguishes this bristle from the corresponding form 
inC. Fauveli. The succeeding region of the body has only the narrow winged tapering bristles 
which, as in front, have a distinct curvature. Toward the posterior end the bristles elongate 
