Pomona College, Claremont, California 11 
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, dis- 
tinguishable 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 separ- 
ated 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. 
LEODICID = 
Leodice monilifer sp. nov. 
Yellow in color, Body strongly narrowed caudad. Prostomium short and broad. 
The palpal lobes large and rounded, bulging conspicuously forward and ventrad; 
separated by a deep furrow. ‘Tentacles in a slightly curved transverse line, the outer 
paired tentacle on each side lying a little farther forward than the inner. Cerato- 
phores very short and not broader than bases of styles, exceeded by the first segment 
of style which about equals the next two in length. The styles in general strongly 
moniliform, the articles short and well rounded. The styles in types short but not in 
any case certainly complete; the number of articles present from nine to twelve. The 
peristomium much longer than the prostomium than which it is also clearly wider and 
