860 
BULLETIN OF THE UNITED STATES FISH COMMISSION. 
The orbito-antennal area varies in the species assigned to this genus. In C. melanochirus A- Milne- 
Edwards, the upper and lower angles of the orbit are approximate, the intervening space being evenly 
filled by the prolongation of the antennal joint; at the same time the flagellum is distinctly excluded 
from the orbit. In C. pilumnoides (White) the upper and lower angles of the orbit are a little farther 
apart, and the basal antennal joint extends its outer angle into the hiatus, but without filling it or 
reaching the summit of the lower orbital tooth, or excluding the flagellum. In our species the antenna 
is much as in C. pilumnoides, but the orbital angles are farther apart. 
Pilodius flavus Rathbun. 
Pilodius flavus Rathbun, Proc. U. S. Nat. Mus., XVI, 1893, 239. 
Carapace two-thirds _as long as wide, rather convex. 
With the aspect of a Pilumnus. A coating of long yellow hairs does not hide the areolation of the 
carapace, which is evident to the naked eye. Regions well marked. Protogastric lobes partially sub- 
divided by a short longitudinal furrow. Orbital groove distinct. 1M separate, also 1L (very small), 2L, 
3L, 4L, 5L, and 6L; a groove between 
2R and 3R. ' Regions sparingly dotted 
with irregular rough granules; inter- 
spaces smooth. • 
Fronto-ofbital width three-fourths, 
front three-eighths, of width of cara- 
pace. Frontal lobes of middle pair 
rounded, granulated, separated by a 
small U-shaped median sinus; outer 
lobes bluntly triangular, bent down 
and separated from the blunt inner 
angle of orbit by a rectangular notch 
and a groove. Margin of orbit granu- 
lated; two V notches above, a deep 
open external fissure. 
Five antero-lateral spines, includ- 
ing the orbital, which is the smallest; 
Fig. 21.— Pilodius flavus, station 4148, male, a, Dorsal view, x 2. 6, each has one or more accessory spines 
Larger chela, x 2f. or spinules; those accompanying the 
third and fourth spines may be almost 
as long as the primaries. Parallel to the margin is a row of three sharp conical tubercles, opposite 
each of the last three marginal spines. 
Postero-lateral margins converging so that if prolonged they would meet at slightly more than a 
right angle. 
Lower surface of carapace granulated and hairy. Basal antennal joint broadly touching the lobe 
of front; outer angle moderately prolonged and reaching end of inner orbital angle; next joint stand- 
ing in orbital hiatus. 
Ohelipeds in male very unequal, in female slightly so. Spines on upper border of arm (three to 
five), outer surface of wrist (two at inner angle), on upper outer surface of palm in rows (where they 
are more conical), and basal half of dactylus; granules on surfaces and other margins of arm and on 
middle outer surface of palm, one row continued on thumb. Infero-external surface of palm in larger 
chela of male smooth and naked ; in smaller chela of male and both chelae of female the spines and 
hairs cover the whole outer face of palm. Fingers gaping, with spoon tips, prehensile teeth large and 
irregular. Color line of index slanting obliquely downward across the palm equally in both sexes; 
tips of fingers white. 
Legs spinous; largest spines on the upper margin of carpal and propodal joints, and of the meral 
joint of the last pair, and also at the distal end of the merus of the other pairs. 
Color . — Orange yellow. 
Dimensions. — Male, station 4148, length 8.8, width 12.8, fronto-orbital width 9.4 mm.; female, 
station 4162, length 8.8, width 13, fronto-orbital width 9.5 mm. 
