REPORT ON THE ANNELIDA. 
433 
ribs, wide in front and narrow behind. In one or two examples these papillae form 
the anterior angles of an elevated cephalic region, the lateral boundary on each side run- 
ning from the papillae backward to the nuchal plait. The buccal region immediately 
behind is marked by bold transverse ridges, terminated posteriorly by a fold, just in front 
of the branchiae. The latter occur in pairs, viz., two anterior, on the third segment, with 
the axis of insertion directed downward and backward ; and two posterior, on the fourth 
segment, with the axis of insertion pointing downward and forward, in each case viewing 
from the dorsum. The tips of some are cjuite filamentary. 
The first bristle-tuft is small, and lies just below the base of the inferior branchia of 
the front pair ; and the next is placed similarly in relation to the second pair. There 
are fourteen pairs, as in Amage. In structure they also approach the latter, the wing at 
the tip of the bristle being moderately developed. Some in each tuft are shorter and 
more slender, a feature well marked in the first and second series. 
The hooks (PI. XXVIIa. fig. 6) commence on the sixth (fourth bristled) segment as 
in Amage. In shape they somewhat resemble those of the Terebellidse, from their short, 
broad outline. They appear to have four large teeth, though more are generally seen 
from the fact that the second series (for they are double) come in the line of vision, then 
a crescentic notch and an oblique anterior inferior tubercle. The basal margin is convex. 
A process occurs at the junction of the latter with the posterior border. The area 
between the dentigerous edge and the dorsal margin is marked by coarse striae. 
Seventeen hook-papillae occur between the last bristle-bundle and the base of the 
posterior enlargement ; and the latter shows eight others in front of the two long filiform 
anal cirri. 
The body diminishes in a nearly uniform manner from the anterior border to the 
posterior enlargement. The latter (PI. XLVIII. fig. 2) is tumid and elongate-ovoid, the 
dorsum being very convex, and the ventral surface flattened. The hook-pads are confined 
to the latter area, and are not visible from the former. A round papilla occurs at the 
anus on each side of the median line interiorly, the long tajDering cirrus being external 
to each. The function of the j)eculiar anal enlargement is probably connected with the 
expulsion of the fsecal pellets. It is almost bulbous in profile. 
The contents of the alimentary canal in those from Station 156 consisted of whitish 
diatomaceous ooze of a very rich description, only a few minute sand-grains and an 
exceptional Foraminifer being seen. The same diatomaceous ooze occurred in those 
from Station 157, but it also presented not infrequent evidences of Radiolarians, and 
large opaque globular bodies of a yellowish colour by transmitted light with an almost 
prismatic edge or fracture, as if made up of separate fibrous prisms, which, however, 
were not regular. They seemed to resemble Foraminifera. The fine hair-like spicules 
also abounded in the food at both Stations. 
The tubes are stiff, though friable, and are formed of greyish mud, here and there in 
(ZOOL. CHALL. EXP. PART XXXIV. 1885.) LI 55 
