104 
THE VOYAGE OF H.M.S. CHALLENGER. 
The genus is characterised by the condition of the scales, which do not cover the 
dorsum, and by the structure of the bristles. 
The body is somewhat flattened and elongate, and in the preparation devoid of 
pigment. The head is much injured, and all that can be said is that the anterior peaks 
are unusually distinct and firm, and that there are traces of ocular pigment posteriorly and 
laterally. The palpi are short and smooth ; and the antennae are also smooth. Neither 
dorsal nor tentacular cirrus is present. The ventral cirrus is a smooth tapering process 
like the antenna, and reaches beyond the bases of the bristles. The ventral papilla 
is very distinct from the fourth or fifth bristled segment backward. It is a small 
slightly tapered jarocess, and is carried on the inner edge of the foot. ClaparMe 
made the interesting observation that in his Hermadion fragile (a closely allied form) 
this organ opens by a ciliated canal into the interior of the foot near the reproductive 
masses. 
The bristles are pale, translucent, and of moderate length. The dorsal group is 
made up of translucent bristles with but three or four, and in one or two of the shorter 
forms, five prominent though somewhat blunt spines to represent the rows usually seen 
in such structures (PI. Xa. fig. 13, which represents one of the thicker long forms in 
which the spines are less developed than in the shorter kinds). In a few of these 
bristles a thin ridge runs from each side of the spine, apparently the homologue of the 
spinous row. 
The ventral tuft consists of rather long and large translucent bristles, the superior 
having elongated and more distinctly spinous tips, the inferior shorter and broader tips 
(PI. Xa. fig. 14). The termination is somewhat strongly hooked, and beneath is a 
distinct though small secondary process. The spinous rows are numerous and close. 
The inferior setigerous lobe- slopes acutely upward to the prominent cone containing the 
spine superiorly. 
Both sets of bristles are peculiarly translucent, and after preservation in calcium 
chloride numerous granules occur toward the base of the hollow shaft. 
The longitudinal ventral muscles present a well-marked inferior convexity in section. 
The ventral area is of considerable width, but the cords are flattened and indistinct. 
The cuticle and hypoderm are both very attenuate. Ova of various sizes occur in the 
perivisceral chamber, so that the specimen is a female. 
Claparede ^ thought his Hermadion fragile (the Polynoe pellucida of Ehlers) was 
closely allied to Kinberg’s Hermadion magalhaensi, especially as the scales did not 
cover the dorsum ; but a minute examination of all the characters shows that there is 
very little in common, while on the other hand the structure of the foregoing and other 
allied forms demonstrates the necessity for instituting a new genus. The Polyfioe 
longicirra of Schmarda,^ from the southern shores of Ceylon, resembles this group in the 
1 Annel. Chetop., p. 72. 
2 Neue Avirbell. Thiere, I. ii. p. 152, Tab. xxxvi. fig. 309. 
