244 ON THE GENUS NOTOPYGOS. 
Notopygos gigas, n. sp. 
Siboga-exped. Stat. 296, Anchorage off Noïmini (South- 
coast of Timor), surface; 9 specimens. 
Body of an oblong oval shape and a length from 45 to 
75 mm.; number of segments from 33 to 36. Colour pale 
buff, in the middle of the dorsum brown or violet, irregu- 
larly interrupted by a number of white lines; a dark band 
around the base of each notopodium and also the main stem 
of the branchiae dusky coloured. The horizontal plate of the 
caruncle, as well as the palpi have a dark hue, and the 
accessory cirri of the anterior segments show a violet stripe. 
Over the dorsalside of each segment there runs a transverse 
groove, dividing it into an anterior and a posterior area; the 
last one is strongly wrinkled, but the anterior area is smoother 
and usually divided into three triangular fields. Over the middle 
of the ventral side a couple of dark parallel longitudinal 
lines. The caruncle has a plaited crest arising from a 
horizontal plate, with 30 folds along its margin on each 
side; it extends to the 6th segment and is rounded posteriorly. 
The unpaired antenna short, measuring about one third of 
the caruncle; the anterior pair of eyes larger than the poste- 
rior one. 
The mouth seems to be limited posteriorly by the 4th 
segment, that is strongly folded in its middle. The anus 
is situated on the anterior part of segment 25, usually at 
the top of a conical papilla. The branchiae commence on 
the 5th segment. The anal cirri are two club-shaped 
processes, composed of a conical basal joint and a globular 
terminal piece, that has a dark hue. The bristles are 
vitreous; those of the dorsal fascicles with a pale greenish 
hue. The dorsal as well as the ventral bristles are bifurcate, 
smooth, with a yellow tip. The anterior three segments 
only contain denticulated setae with a rather divergent 
fork; they are usually triserrate in the first segment, bi- or 
uniserrate in the next two. 
Notes from the Leyden Museum, Vol. XX XIII. 
