144 
THE VOYAGE OF H.M.S. CHALLENGER. 
Sphserozius, Stimpson. 
Sphserozius, Stimpson, Proc. Acad. Nat. Sci. Philad., p. 35, 1858. 
Body subglobose ; carapace convex, smooth, shining, and neither lobulated nor sul- 
cated on the dorsal surface, except on the postfrontal or epigastric region, where there is the 
usual longitudinal median suture, which reaches the front and is posteriorly bifurcated. 
The antero-lateral margins are shorter than the postero-lateral margins, and are divided 
behind the postero-lateral angles into four serratures or teeth, which are not spiniform, as in 
Pilwnnus. The front is slightly deflexed, about one-third the width of the carapace, and 
is divided by a median notch ; its anterior margin is not separated by a notch from the 
interior angle of the orbit. The orbital margins are small, entire. The longitudinal ridges 
of the endostome or palate are not very prominent. The post-abdomen in the male, and 
in the single specimen I have seen of a female, is distinctly seven-jointed. The eyes are set 
on short thick pedicels. The basal joint of the antennae is very short, and does not 
nearly reach the front ; the following joint is slender and just attains the infero-lateral 
frontal angle. The ischium of the endognath of the exterior maxillipedes is not produced 
at its antero-internal angle ; the merus is distally truncated, with the antero-external angle 
rounded and not produced, and the antero-internal angle scarcely emarginate. The straight 
exognath reaches the antero-external angle of the merus of the endognath. The chelipedes 
are robust, unequal ; carpus bluntly toothed on its inner margin, palm rounded above ; 
lingers distally acute and dentated on the inner margins. Ambulatory legs slender and 
of moderate length, with the joints smooth, hairy; dactyli straight, with a well-developed 
terminal claw. 
The nearest ally to this genus is, I think, Pilumnopeus, A. Milne Edwards, 1 from 
which it is mainly distinguished by the smooth and narrower carapace, which is not 
lobulated, the absence of the exterior orbital hiatus, and the shorter basal antennal joint. 
Pilumnopeus should not, perhaps, be regarded as generically distinct. 
The following species have been referred to Sphserozius by its author : — 
Sphserozius dispar (Dana). Sooloo Sea. 
Sphserozius nitidus, Stimpson. Hong-Kong ; Kobe, Japan, 50 fathoms. 
Sphserozius nitidus (PI. XII. fig. 4). 
Sphserozius nitidus, Stimpson, Proc. Acad. Nat. Sci. Philad., p. 35, 1858. 
Kobd, Japan, lat. 34° 38' 0" N., long. 135° 1' 0 " E. (Station 233a), in 50 fathoms 
(a female). 
1 Ann. S'jc. Entom. France, ser. 4, yol. vii. p. 277, 1867. 
