70 
THE VOYAGE OF H.M.S. CHALLENGER. 
on tlie lateral eminence in front of these. All are seen from the dorsum. The 
tentacle is longer than the palj^i, and shows a slight enlargement below the veiy long- 
filiform tip. It springs from a large basal segment which occupies the middle of the 
anterior margin of the head. The antennge are subulate, and their tips reach the 
terminal third of the palpi. The latter are of moderate length, with tapering tips. 
Only very minute papillse (seen under a power of 350 diameters) occur on one side, 
so that they are comparatively smooth. The tentacular and dorsal cirri agree with 
the tentacle, the long filiform tips of the cirri projecting beyond the bristles. The 
dilated terminal region has rather long clavate papillae, but these organs diminish 
above and below this part. The subulate ventral cirrus is furnished with shorter 
clavate papillae. 
There are fifteen pairs of scales, and they completely envelop the dorsum after the 
manner of Ipliione. The first scale is rounded, dotted with the black spines, and 
bordered with rather long clavate cilia. The others (PI. XVII. fig. 4) are studded with 
similar chitinous spines, the larger of which have the extrinsic blackish pigment, and 
cilia along their outer border. In section the tissue of the scale is dense. The scales 
are proportionally large and massive. They diminish in thickness from the surface of 
attachment to the margin. 
The dorsal branch of the foot has a series of somewhat slender elongate bristles 
with comparatively short pointed tips (PI. VIIIa. fig. 1, the figure representing a stoutish 
form, as some are much more slender). The rows of spines are well marked and 
distinctly separated. The longer forms are extremely slender toward the tip. 
The ventral bristles again have simple hooked tips like those in Eunoa} with well- 
marked row of spines. On the whole the terminal region is short (PI. VIIIa. fig. 2). 
The ventral area between the oblique muscles is of moderate size, and the cords are 
ovoid. The ventral cuticle is quite smooth. This form approaches Lagisca in the 
structure of the head and scales, but no bifid bristle occurs in the inferior group. 
It quite differs from Iphione in the character of the dorsal bristles and other particulars. 
It also comes near to Polynoe macrolepidota of Schmarda, from Auckland and New" 
Zealand, but the spines on the scales of this species are much longer, and the cilia more 
abundant on the edge, as well as longer. Schmarda’s figures ^ of the bristles are deficient 
in precision. 
1 I see no disadvantage in adopting Malmgren’s genus Eunoa, on structural grounds. Dr. Hansen (Norske 
Nordhavs-Exped., p. 24) seems to have overlooked the essential characters which are common throughout the Polynoidas, 
e.g., the general correspondence of the dorsal cirri with the tentacle and tentacular cirri. Thus he makes a new species 
{Polynoe islandica) for a form in which the former processes are smooth while the latter are ciliated. If we hear in 
mind the characters just mentioned, it is probable that this imperfect specimen is an abnormal example of Eunoa xrstedi, 
Malmgren. 
2 Neue wirbell. Thiere, I. ii. p. 155. 
