Pomona College, Claremont, California 15 
the thirteenth or fourteenth segment. ‘The prostomium is broadly subtrapeziform, nar- 
rowing forward and with the anterior margin varying from slightly convex to mesally 
indented as is the case in the type; dorsal surface nearly flat, simply marked with two 
furrows, or sometimes with the median caudal region between furrows elevated. Peri- 
stomium with anterior margin above more or less concave, its median length about 
equal to that of the second segment, which is also ordinarily bowed caudad. In the 
neuropodia of the anterior region the postsetal processes are broad, distally rounded, 
thick lips which are prominent; in the posterior region these become narrowly conical, 
elongate, distally pointed processes. The postsetal processes of the notopodia in the 
anterior region are thick, short cones which increase in length in going caudad, in the 
posterior region being very elongate. The branchi# begin on the thirteenth or four- 
teenth segment as short processes but become abruptly longer, basally thick and distally 
pointed processes much thicker than the postsetal processes of the notopodia and 
exceeding these in length; they are widely separated and, while curving in somewhat 
mesad, do not come in contact, leaving much of the mid-dorsal region naked. They 
continue to the end of the body. The neuropodial sete of the anterior region are ar- 
ranged in three subvertical series and form a patch twice as high (dorsoventrally) as 
long (cephalocaudally). The stout sete of the posterior row are mostly four in num- 
ber, less commonly three or five. These coarse sete are not at all clavate as in elongata 
and are not roughened or cross-ridged above the curve as in robusta; the terminal 
region above the curve longer than in the later species. The sete of the other series 
are more curved than in robusta and are abruptly contracted farther from the body. 
the contraction stronger but the one edge similarly roughened or denticlated with cross 
lines. At the ventral end of the series a small patch of ordinary, camerated, capillary 
sete resembling the notopodials. The body is broad anteriotly and narrows to the 
posterior end. Dorsal surface flat and the ventral convex as usual. Number of seg- 
ments in the type one hundred and thirty-six. Color in general pale brown; at black 
spot at base of each branchia at least those of posterior region, in front and behind 
and the proximal part of branchia often darkened. 
Length, 27 mm.; greatest width, 2.4 mm. 
Type—M. C. Z. 2, 161. 
Scoloplos acmeceps sp. nov. 
Resembling S. armiger (O. F. Miller) in general structure. A less deeply pig- 
mented species easily distinguished from this northern form in wholly lacking the 
ventral papille (neurocirri) present in the latter below the parapodia of about the 
eighteenth to thirtieth segments. The prostomium is similarly elongate and pointed 
but is more slender; it is borne at the end of the peristomium which has the form of 
a truncate cone. The branchie begin anteriorly in the same way as very slight eleva- 
tions and increase quickly to long ligulate forms; but the first one appears on the 
sixteenth or seventeenth setigerous segment instead of on the twelfth or thirteenth as 
usual in armiger. The fully developed branchie are obviously narrower than typical 
for the latter species. The lobes of the parapodia are in general similar though they 
do not become obvious so far forward. In the second division of the body the ventral 
lobe is similarly elongate and bifid at the tip with the inner or more dorsal lobe the 
longer; but the lobes are characteristically more divergent, thinner and more slender. 
The first bifid neuropodial lobes appear on the twenty-first setigerous segment. The 
