EEPORT ON THE ANNELIDA. 
219 
This species quite differs from Nereis marionii in regard to the tentacles, the 
tentacular cirri, and the paragnathi. It is also distinguished from Nereis limbata, 
Ehlers,’- from the east coast of North America, by the paragnathi. It more nearl}^ 
approaches the Nereis succinea of R. Leuckart, from the. North Sea (Heligoland, 
Cuxhaven, &c.), but its paragnathi also deviate. Thus, instead of the structure given 
above, I. in Nereis succinea has three arranged antero-posteriorly ; II. forms a double 
row, and so with the others. In the same manner it is separated from Nereis vexillosa, 
Grube,^ from the west coast of North America. All these forms, however, belong to the 
same group. 
Nereis atlantica, n. sp. (PI. XXXV. figs. 1, 2, 3 ; PI. XVIa. figs. 10, 11). 
Habitat. — A single example was procured at St. Vincent, Cape Verde Islands, July 
1873. 
Head about the same length as breadth ; tentacles only about half the length. Eyes 
large, the pairs almost touching on each side, all with lenses. Tentacular cirri compara- 
tively short, the longest reaching the fifth segment. Paragnathi — I. a single large tooth ; 
II. each with five to seven teeth ; III. a central and about eight surrounding teeth ; 
IV. groups twice the area of II. ; V. two narrow, horny ridges, and behind one a small 
posterior tooth (in extrusion) ; VI. absent ; VII. and VIII. in three ranks at considerable 
intervals. Maxillse dark brown ; four teeth below the fang. First segment broader than 
the next. Feet have conical lobes with truncated tips anteriorly. The second lobe 
increases characteristically posteriorly. Dorsal cirri short. Setose bristles with long- 
slender extremities ; falcate with a convex anterior (setose) margin along tip. 
A form about 88 mm. in length and about 4 '5 mm. in breadth at its widest part. 
The body presents the ordinary appearance in front, but the posterior region is pale, 
from the development of the reproductive elements. 
The head '(PI. XXXV. fig. 1) is somewhat triangular, with the apex truncated 
anteriorly ; and its antero-posterior diameter is only slightly more than the transverse 
at the base posteriorly. The anterior part of the head is marked by minute pale points 
or pores. The tentacles are short and subulate,' being little more than half the antero- 
posterior diameter of the head. The tentacular and other cirri are comparatively short, 
the longest reaching the fifth foot. The posterior half of the lateral cephalic margin is 
occupied by the pigment of the eyes, which almost touch each other. The anter or pair 
are decidedly larger, and have the elongated lens in the line of the margin, so that the 
eye looks forward and outward. The pigment is mostly on the dorsal side of the lens, 
1 Die Borstenwiinner, Bd. ii. p. 567. 
2 Eeise u. Norde und Oste Siberiens, Mem. Inst. Samns Etmng. St. Petersb., 1858, Sep. AIkI. p. 4, pi. ii. figs. 1, 5, 6. 
