296 
THE VOYAGE OF H.M.S. CHALLENGER. 
and thirtieth a singde long brownish hook appears. The dorsal cirrus presents the 
usual gradation in length, from head to tail, and is on the whole rather short and 
thick. The anterior ventral cirri have a large tongue-shaped process. 
The bristles of the larger examples are generally more or less abraded. The simple 
superior bristles have many adherent particles. The brush-shaped forms show about a 
dozen processes at the tip. 
The compound bristles (PL XXIa. fig. 4) have a wide bifurcation, and the inferior 
process is small. The shafts are somewhat curved, and have fine serrations along the 
margin of the slightly dilated tip. In the posterior segments the shape of the 
terminal region of the bristle alters, the inferior fang being large and prominent, 
while the wing is continued upward and outward from the distal tooth by a thickened 
process or rib. 
The dark brown inferior hook (PI. XXIa. fig. 5) in the setigerous region of the foot 
has a small terminal process above a moderately large fang, the usual guard or wing 
being in front. The tips of the spines of the posterior feet have a peculiar clavate 
parasite (apparently Protozoan) growing in launches. 
In the intestine are one or two minnte shells resembling Odostomia, and sandy mud 
containing sponge-spicnles. 
The specimens from Station 162 are somewhat less than the foregoing, and are 
distinguished by the pale ring bearing the second foot. This segment appears to have 
been white during life. The anterior region corresponds, only the tentacular cirri are 
shorter. The dental apparatus is similar, though the colour is less deep. The mandi- 
bular denticulations are feebly developed. The branchige commence on the sixth 
segment, and have two divisions. They are somewhat shorter throughout than in the 
previous examples, and their divisions less fusiform, but these differences may be due 
to size (PL XXXIX. fig. 15, tenth foot). The hooks and bristles are similar, and od 
the whole they may be regarded as varieties of the former. In the intestinal pellets of 
these are sandy mud with numerous sponge-spicules and Diatoms, and larger tough 
masses of a fine Polyzoon with bird’s head processes. 
A i)edicellaria is fixed to the under surface of the palp of one of the Annelids. 
Both cuticle and hypoderm are fairly developed. The dorsal longitudinal muscles 
are much more massive than the ventral. The nerve-area is rounded, and the neural 
canal is placed close to the circular muscular coat. The usual brownish granular mass 
occurs above the cords, and this differs from the contents of the blood-vessels in the 
more distinctly granular condition. The fine jDarallel transverse branches of the blood- 
vessels on the branchial pinnae are well seen in this form. 
The chief difference in the sections of the specimen from Bass Strait is the dilatation 
of the neural canal, and the massive condition of the oblique muscles. Granular masses 
(probably reproductive elements) occur external to the ventral longitudinal muscles and 
