REPORT ON THE ANNELIDA. 
480 
appendage. They show the transverse articulations or cell-like divisions of the stem 
very distinctly. The pinnse are long and slender, but diminish in size below the 
attenuate and bare tip. No closely set rudimentary series exists, as in some of the other 
forms, below the commencement of the terminal process. On each side is a bifid and 
comparatively short tentacle, the basal region being broad and the divisions filiform. 
The anterior tufts present dorsally a few bristles with bent tips and a well-marked 
wing (PI. XXIXa. fig. 23). The tip is only moderately lengthened. The inferior series is 
formed of paddle-shaped bristles (PI. XXIXa. fig. 24) with a slender median prolongation. 
The posterior bristles, as usual, are distinguished by the proportionally elongated tips. 
The hooks (PI. XXIXa. fig. 25) have the crown directed forward, so that the dorsal 
convexity is marked. The anterior inferior projection or “breast” is much less bulky 
than in Sahella zehuensis, and there is no noteworthy convexity in the ventral line. The 
anterior inferior curve is thus more acute than in the previous forms. 
The contents of the intestine are a few Diatoms, and a peculiar translucent fluted 
dotted shell of unknown relations, with sandy mud. 
Both examples are fixed to the test of an Ascidian, and possess somewhat hard 
chitinous tubes, strengthened anteriorly by minute grains of sand and an occasional 
sponge-spicule or calcareous articulated fragment. The test of the Ascidian is also 
coated with sand and mud, and has in addition filamentous processes of secretion and 
sand as in Pelonaia. 
The hooks of Dr. Baird’s Sahella occidentalism from St. Vincent, West Indies, some- 
what resemble those of this form, but the dorsal curve differs inferiorly, and the colora- 
tion of the branchiae also diverges. 
Sahella hipwictata, Baird (PI. LII. fig. 4 ; PI. XXXa, figs. 1-3). 
Sahella hipunctata, Baird, Journ. Linn. Soc. Lond., vol. viii. p. 158. 
Habitat. — Found between tide-marks at St. Thomas, West Indies, March 23, 1873. 
A small specimen, measuring about 26 mm. in length, including the branchiae, 
which extend to 8 mm. The diameter anteriorly is about 3 mm. 
The body is somewhat broad and flattened in front, and tapered from before back- 
ward. A purplish-brown spot occurs at the base of each foot dorsally and ventrally, 
with the exception of the ventral series of the anterior region. The pigment in the latter 
is in the form of a band along the anterior margin of each hook-row, thus giving a marked 
character to the region. The dorsal surface of the body presents a furrow, but none 
exists on the ventral aspect. 
The cephalic region dorsally has a median furrow, on each side of which is an 
elevation or crest with a purplish-brown speck. The collar commences opposite the 
second bristle-bundle, and the lamella is coloured purplish-brown from this point forward 
(ZOOL. CHALL. EXP. — PART XXXIV. 1885.) LI 62 
