154 
THE VOYAGE OE H.M.S. CHALLENGER. 
Pilumnus minutus (•?), de Haan, var. hirsutus. 
1 Pilumnus minutus, de Haan, Crust, in v. Siebold, Fauna Japonica, pp. 19, 50, pL iii. fig. 2, 1835. 
Pilumnus hirsutus, Stimpson, Proc. Acad. Nat. Sci. Philad., p. 37, 1858. 
,, „ Miers, Proc. Zool. Soc. Lond., p. 31, 1879. 
Specimens are referred to this species from Kobe, Japan, lat. 34° 38' 0" N., long. 
135° l',0" E., 5.0 fathoms (Station 233a). 
In the specimens I have examined there is commonly a small accessory spinule on the 
antero-lateral margins, situated behind the spine at the outer angle of the orbit. 
Adult $ . Lines. Millims. 
Length of carapace, nearly ...... 4 8 
Breadth of carapace, . . . . . . . 5 10 
As the original description of this species by de Haan is very brief, I append the 
following, based on the largest male in the Challenger series. 
The carapace is moderately convex and transverse, and, as well as the ambulatory 
legs, is covered with a short greyish-brown pubescence, interspersed with longer hairs ; 
the regions are not defined, and the dorsal surface is not distinctly granulated. The 
front is divided by a median notch into two somewhat obliquely truncated lobes, whose 
anterior margins are not spinuliferous. The orbits are moderately large ; their 
superior margins have very obscure indications of a notch or sinus, their inferior 
margins are denticulated, the denticles becoming more prominent and spinuliform 
at the interior subocular lobe, and are armed with four small spiniform teeth, the 
second of which in this specimen (but not usually), bears a very small accessory 
spinule ; there is no spinule upon the subhepatic region. The chelipedes are very 
unequal, with the merus short, trigonous, and denticulated on the superior and anterior 
margins, the carpus armed with granules, which tend to become spinuliform, on the 
superior and exterior surface ; palm (in the larger chelipede) granulated above and at 
the base, but smooth over nearly the whole of its outer surface ; in the smaller chelipede 
it is covered, both above and externally, with conical, acute granules or small spines ; 
dactyli granulated above at the base (but very obscurely in the larger chelipede) ; fingers 
toothed (the dactylus rather obscurely), on the inner margins. The ambulatory legs 
are clothed, especially on the last three joints, with greyish pubescence, interspersed with 
longer hairs, but are not armed with spines or spinules. 
In 1879 I regarded Stimpson’s species, Pilumnus hirsutus , as distinct from Pilumnus 
minutus, de Haan, on account of the acute antero-lateral marginal teeth, and the denticu- 
lated inferior orbital margins, but I am now inclined to regard Pilumnus hirsutus as a 
variety only of Pilumnus minutus ; the diagnosis of de Ilaan’s species is, however, very 
short and the figure insufficient. 
