264 
THE VOYAGE OF H.M.S. CHALLENGER. 
The structure of the dental apparatus of this genus, as Elders^ clearly points out, 
leans to the type of the Eunicidse, and diverges from that in the Lumhrinereidse. The 
present species approaches the Neinatonereis unicornis of Schmarda^ somewhat closely, 
but the condition of his figures, and the want of definition in his description leave no 
course except separation open, until, for instance, the discrepancies of the maxillse and 
dental plates are explained. 
Nematonereis, sp. (PI. XXXVII. fig. 10; PI. XIXa. figs. 1, 2). 
Habitat. — Found on the beach between tide-marks at Sea Point, near Cape Town. 
A fragment, apparently consisting of the tail of a member of the present group. 
The segments of the body are marked with great distinctness, the junctions 
forming deep depressions, wide at the anterior part of the fragment, and narrow 
behind. Each foot (PI. XXXVII. fig. 10) bears dorsally a small cirrus, which hardly 
projects beyond the line of the setigerous region. Inferiorly is a minute ventral cirrus, 
which, as usual, is proportionally more massive than the upper. Superiorly are a series 
of elongated tapering bristles without an evident wing, and a number of short brush- 
shaped forms (PI. XIXa. fig. 1) characterised by their comparatively large and broad 
tips. Inferiorly are jointed bristles (PI. XIXa. fig. 2) with short terminal pieces, 
showing a bifid terminal fang and a large one beneath, while the end of the shaft is 
dilated. In addition the foot bears an attenuate brownish spine, and a long brownish 
bifid hook, with a short terminal and a larger subjacent fang. 
This fragment appears to be most closely related to the foregoing. 
Nematonereis, s^x (PI. XXXVII. fig. 11; PI. XIXa. figs. 3—5). 
Habitat. — Procured at St. Vincent, Cape Verde Islands, July 1873, probably on 
shore, though this is not stated. 
A fragment of the posterior end of a form allied to the foregoing. The segments 
of the specimen are as distinctly marked as in the posterior end of Lysidice ninetta, 
and it is about the same size as an average example of the latter. 
The foot (PI. XXXVII. fig. 11) has dorsally a minute cirrus, which does not project 
so far outward as a vertical line touched by the tip of the setigerous region. The 
latter is somewhat (though irregularly) conical, with the brownish spine projecting 
through the apex. Inferiorly is a thick lobate ventral cirrus, which (from the shorter 
inferior line of the setigerous lobe) projects further outward than the dorsal cirrus. 
1 Die Borstenwurmer, ii. p. 373. ^ Neue wirbell. Tliiere, I. ii. p. 119, Taf. xxxii. fig. 254. 
