REPORT ON THE ANNELIDA. 
187 
Length about 16 mm.„ and breadth, from tip to tip of the long feet and bristles, from 
7 to 8 mm. 
The body appears to be clavate, the anterior end being large, and the posterior tapered 
to the anus, which is situated dorsally. The upper surface is rounded, the ventral 
marked by the usual longitudinal groove. It does not appear that the peculiar tapering 
posteriorly is due to reproduction of the tail. 
The head (PI. XXIX. fig. 3) projects forward from an overlapping collar formed by 
the first segment, and is mapped out and mottled in a peculiar way. Thus the central 
region is curved forward in front, and speckled with dark pigment anteriorly, while the 
lateral region on each side is formed by an elevated area, sloping from behind forward 
and outward like the arms of a V. A crescentic band of dark pigment is situated at the 
posterior border of each of the latter, in front of which comes a pale belt followed by the 
tinted region on which the eyes are situated. The anterior eyes are considerably larger 
than the posterior. Both have reddish-brown pigment in the preparation. In front of 
the eyes the ridges subside into the general level of the snout. Two tentacles occur on 
each side, a larger external with a distinct segment at the tip, and a smaller internal 
filiform one without such differentiation. 
The buccal region bears dorsally three cylindrical processes, the third on each side 
being bent up as if for the support of a scale. All these, however, are probably the 
basal processes of cirri, and they increase in size from the first to the third. Interiorly 
are also three basal processes for cirri, but these are not symmetrical with the others, the 
last being in a space behind the third dorsal process. The second and third possess a 
ventral cirrus. Behind the latter comes the first bristled foot, which bears a dorsal cirrus 
nearly as large as those in front, a slender setigerous process, and a delicate ventral cirrus. 
The next foot shows a trace of a superior division as well as a dorsal cirrus (PI. XXXIII. 
fig. 2, anterior foot before the normal shape of the dorsal division is attained), and, by 
and by, the foot is completely formed. In the fully developed condition a slender 
elongated dorsal cirrus is attached to a basal segment, while two delicate blackish 
spines support a group of elongated, tapering, simple bristles (PI. XVa. fig. 5), which, 
except at the curved and slender tip, are marked by a close series of transverse striae. 
The inferior division of the foot is largely developed, and has a conspicuous, fan-shaped 
fascicle of pale straw-coloured, stoutish, slightly curved bristles, with characteristic terminal 
pieces. When viewed laterally the shafts present a considerable increase in size toward 
the tip, and are marked by longitudinal, or obliquely longitudinal lines, and fine transverse 
strise. The terminal appendages decrease in length from the superior to the inferior 
border of the foot. Each is articulated, as in the Nereidse, by a somewhat pointed end, to 
a socket at one side of the tip of the shaft, and has the shape of a broad and slightly 
curved' sword-blade, wide at the base and narrow toward the tip. The latter is bifid, with 
a terminal hook, a stout knob beneath, and a slender elongated spur or process projecting 
