Report on the zoological collections made in the Indo-Pacific Ocean ...

CRUSTACEA. 223be at once distinguished by the following characters :—The carapaceis broader in proportion to its length, and its anterior parts clothedwith a close velvetj' pubescence, which also extends over the upperand outer surface of the wrist and palm of the chclipedes ; the twoposterior teeth of the antero-lateral margins are more distinctlyspiniform, the basal antennal joint does not nearly reach to the subfrontalprocess ; the granulations of the wrist and palm are muchmore inconspicuous, those of the outer surface of the palm appear,through the pubescence, to be arranged in four distinct longitudinalseries (fig. c) ; the ambulatory legs are slenderer.Colour (in spirit) purplish brown, hairs cinereous.Length of thelargest specimen, a female, about 5| lines (nearly 12 millim.),breadth about 7| lines (16 millim.).There is a male in the first collection from Port Denison, 4 fms.(No. Ill), and a female in the second collection from ThursdayIsland, 4-5 fms. (Xo. 1G5).Mr. Haswell has described a species {Pllumnus inermis*) fromPort Jackson which apparently resembles this and the precedingspecies in having the anterior parts only of the carapace clothedwith hairs, which are long as in P. semilanatus. It differs, however,in the less distinctly toothed antero-lateral margins of thecarapace, in the form of the front, which is entire, not notched, andin the disposition of the granules of the chelipedes, both from P.semilanatus and P. seminmlus.Pllumnus Icevimanus, Danaf, is apparently allied to this and theforegoing species, but has the carapace almost wholly naked, andthe larger hand rounded above and quite smooth, with only somefaint traces of minute tubercles toward the base. It has been recordedfrom Borneo and New Caledonia.In Pllumnus nitidns, A. M. -Edwards +, from New Caledonia,which is another nearly allied species, the two anterior teeth of theantero-lateral margins of the carapace are obsolete,59. Pllumnus cursor ?? Pllumnus cursor, A. M.-Edwards, Nuuv. Archiv. Mus. Hist. Nat.ix. p. 244, pi. ix. fig. 4 (1873).In the specimen I thus very doubtfully designate the carapaceis nearly smooth, with the anterior portion moderately deflexed,antero-lateral margins much shorter than the posterolateral,which are nearly straight and convergent posteriorly ; bothcarapace and limbs are scantily clothed with very short hairs,among which a few longer hairs are interspersed ; the frontal lobesare divided by a rather deep and wide median fissure ; the anterolateralmargins are armed with three spines, besides a smaller butdistinct spine at the exterior angle of the orbit. The basal antennal* Proc. Linn. Soc. N. S. Wales, vi. p. 544 (1881) ; Cat.alogue, p. 70 (1882).t Crust. U.S. Expl. Exp. xiii. p. 237, pi. xiii. fig. 11 (1852).Nouv. Arch. Mus. ix.Xp. 249, pi. x. lig. 2 (1873).