REPOET ON THE ANNELIDA. 
221 
The fifty-seventh foot (PL XXXV. fig. 3) shows greater differentiation, for the 
elevation at the base of the cirrus appears to form a part of the superior lobe. The 
dorsal cirrus scarcely reaches the tip of the latter. The second lobe is proportionally 
larger and more gibbous beyond the constriction at the base. The inferior setigerous 
division is more elongate, and the collar (which assumes a button-shape in ordinary 
views) more prominent. The ventral lobe is somewhat less than in front ; while the 
cirrus has slightly increased in length. 
The setose bristles (PL XVI a. fig. 10) have long, slender, tapering tips. The falcate 
forms (PL XVIa. fig. 11) have simple hooked tips with setse on the margin below. 
The tail terminates in four elongate cirri, two on each side of the anus. 
In the intestinal canal are numerous fragments of small Crustacea, and minute 
pieces of cinders. 
The nerve-cord lies in the angle between the insertions of the oblique muscles, and 
shows three large neural canals, a superior and two lateral. The superior fold of the 
ventral longitudinal muscles is moderate. 
This form appears to come under Kinberg’s group Perinereis, B,^ with three 
paragnathi in V., and under division /3, where only a single tooth occurs in L, his example 
being Perinereis hedenhorgi, from Alexandria. An essential divergence from Perinereis, 
however, is the absence of paragnathi VI. This species most nearly approaches the 
Nereis jioridana of Ehlers, as found by Langerhans ^ along with Nereis cidtrifera, Grube, 
under stones on sandy gravel between tide-marks at Madeira. It differs from this, 
however, in the comparative length of the tentacles, and in the absence of paragnathi 
VI., which in Nereis Jioridana form “ eine grosse quer lineare,” while the arrangement of 
the other groups also diverges. The general outline of the feet, however, as well as the 
structure of the bristles, show the close proximity, and further investigation may clear up 
the present ambiguity. 
Nereis {Platynereis) dumerilii, Aud. and Ed., var. 
Habitat. — Two small and imperfect specimens were procured at St. Vincent, Cape 
Verde Islands, July 1873. 
These specimens bear a very close resemblance to Nereis dumerilii, Aud. and Ed., 
though the second lobe of the foot slightly differs, and the setose bristles show less 
distinct serrations. The falcate forms are apparently less hooked. The eyes rre also 
larger. The paragnathi, however, seem to correspond with those in the typical form, 
which extends from Shetland and the Baltic to Madeira, where Prof. Langerhans 
says it is not uncommon. 
^ Op. cif., p. 175. 2 Zeitsclir.f. wiss. Zool, Bit xxxiii. p. 289, Taf. xv. fig. 24, 1880. 
