152 
THE YOYAGE OF H.M.S. CHALLENGER. 
moreover, shows that the outer border in the anterior scales is very prettily marked by 
regularly arranged areolse. The great nervous ganglion (situated behind and somewhat 
exterior to the umbilicus) and its branches are seen with remarkable clearness in this 
species (PI. XXV. fig. 8), and are worthy of minute study. The general surface of the 
scale is granular by transmitted light. 
The first foot, as usual, is directed straight forward, and bears on the superior division 
a long tuft of tapering bristles which are only distinctly serrated in the upper series of 
the group. The rest are much more minutely hispid toward the tip. The inferior 
division, again, has a similar long tuft of tapering bristles, but the serratures, if present, 
are barely discernible. Both groups are thickly studded with somewhat large clear 
globular bodies, a2jparently of a fungoid nature. 
The second foot (which carries the first scale) puts on the character of the jDosterior 
to a greater or less extent. The dorsal branch has a grouj) of very long j^fipillse (about 
five in number). Only the bristles nearest the body, however, are distinctly serrated. 
The inferior division shows bristles with the usual canaliculated ti^DS, though they are 
more slender than those which follow. 
The third foot, as in the former S2)ecies and other Leanirce, bears the long and 
characteristic cirrus, which stretches considerably beyond the tij) of the first foot in a 
line straight forward. It is an elongated, smooth, tajDering process, and has at its base 
externally a globular enlargement. The 2>recise homologies of this 2>rocess are interesting. 
It quite differs from that found in Sthenelais and Sigcdion (for in the latter genera this 
segment bears only a minute process attached to the external border of the dorsal, 
tubercle). If the external enlargement of the basal region re2)resent the dorsal 
tubercle in the other forms usually associated under the Aphroditidae of Savigny, 
Audouin and Edwards, Grube, and others (that is using the term in its widest sense), 
then the long cirrus on the third foot of Leanira is not homologous with the succeeding 
branchial ones, which arise from the exterior of the dorsal tubercles for the scales. In 
the Polynpidae, for instance, the dorsal cirri S2)ring from a point altogether external to 
the tubercles. 
When the feet are fully formed the dorsal bristles are similar to those in Leanira 
magellanica. The ventral bristles (PL XIIIa. fig. 1) are longer than in the latter form, 
and thus they and the dorsal are more nearly equal in length. Moreover, while 
the shafts are somewhat longer than in LeanL'a magellanica, the tij)S are, compara- 
tively, somewhat shorter. A well-marked branchia, richly ciliated interiorly, occurs on 
every foot, and bears ventrally a process at its base like a diverticulum. In one or two 
instances a branch as long as the branchia takes origin from the latter. The same 
arrangement of ciliated pads occurs as in Leanira magellanica, viz., one under the 
branchia, a second long one, and a third broadly clavate or fan-shaped process on the 
dorsum of the foot. 
