_Nereis latescens_ sp. nov.
Allied to _N. vexillosa_ (Grube) but a much smaller species readily
distinguishable superficially through the presence of purplish markings
on the prostomium and anterior segments, by the form of the appendages,
and particularly by the presence on region V of the proboscis of a
single large conical tooth such as is present in various epitokes.
The prostomium is marked above by a large purplish area germinate by
a narrow median longitudinal yellow line. Eyes black. On the anterior
segments, above on each side a transverse purplish stripe along
anterior and one along posterior border and across the dorsal region, a
shorter but broader stripe a little in front of the middle of segment.
The body otherwise yellowish. Eyes exceptionally large, and those of
each side very close together. Tentacles close together, slenderly
cylindrical, moderately narrowing distad, shorter than prostomium
and not extending beyond end of proximal joint of palpi. Paragnatha
in general as in _vexillosa_; area I with but a single tooth; II,
III and IV with numerous teeth in a patch on each; V with a single
exceptionally large tooth; VI with four teeth in a quadrangle; VII
and VIII with teeth in a band across ventral and lateral surface in
which the proximal ventral teeth are smaller than the distal as in
_vexillosa_. Peristomium shorter than prostomium and than the next
two somites combined; divided by a transverse furrow. Tentacular
cirri short; the ventral ones subequal, less than half the length of
the dorsals, which are also nearly equal to each other; more or less
flattened; cirrophores short. A typical parapodium presents three stout
conical lobes additional to the setigerous ones; of these the dorsal
one in the anterior region is stoutest, but becomes more slender in
the posterior region. Both notocirri and neurocirri proportionately
very slender. Anal cirri about as long as the dorsal tentacular cirri,
flattened.
Number of segments, sixty-two.
Length of types, 20 to 23 mm.
Type--M. C. Z. 2, 152.
Taken among hydroids.
_Nereis mediator_ sp. nov.
This species also resembles _N. vexillosa_, though apparently a
normally much smaller form. It is, so far as evidence at present
accessible to me indicates, distinguishable from that species in having
a narrow band across the anterior border of the dental band of VII
composed of much finer denticles instead of having the anterior teeth
large and the posterior ones reduced. The paragnatha are fewer than in
_vexillosa_, those of II, e. g., being in fewer (usually three), less
oblique and more separated series and those of VI in all the typical
specimens being three in a triangle or four instead of from six to
nine or more in a crowded patch. No colored markings. The tentacles
proportionately thicker and obviously closer together. Tentacular cirri
shorter. Notocirral laminae of the middle and posterior regions much
less elongate and flattened with their ventral conical lobe much more
pronounced throughout, more as in the smaller specimens of _vexillosa_.
Anal cirri short. Number of segments up to seventy.
Length, to 60 mm.
Type--M. C. T. 2, 153.
This is doubtless the same form as recorded by Dr. Moore from San
Diego as _N. vexillosa_ in Proc. Acad. Sci. Phil., 1909, p. 244.
It is undoubtedly close to that species; but as all the specimens
which I have seen, and apparently also those studied by Moore,
differ constantly in the features above mentioned from specimens of
_vexillosa_ from more northern localities on the Pacific coast, etc.,
the form is maintained as distinct. A single heteronereis female is
among the specimens from Laguna Beach.