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

;292 COLLECTIO^^S from. MELANESIA.beyond the rostrum and bear two flagella, whereof one is considerablythickened and is bipartite at its extremity ; the antennalpeduncles are short, with the last joint longer than the preceding ;their basal scales ovate, much longer than the peduncles, and withoutspinules ; rounded and ciliated at the distal ends ; the tlagellaare shorter than the animal, with the joints nearly naked ; the twolast joints of the outer maxillipcdes are slender, setose, and togetherlittle longer than the antepenultimate joint, which, like thepreceding, is moderately dilated. The anterior legs are slender, withthe wrist elongated and about twice as long as the palm and fingerstaken together ; the second chelipedes, although larger than the preceding,are yet slenderer than in many allied forms ; the joints arewithout spines ; the right leg a very little more robust than the leftthe merus or arm about as long as the ischium and little longerthan the carpus, which is rounded above and below and not half aslong as the palm ; the palm is smooth, rounded above and below,very slightly compressed ; the fingers rather more than half thelength of the palm, with thin inner edges, incurved and acute at thetips, and each armed with a tooth near the base on the inner margin,that of the dactyl being the larger ; in the left chelij^ede the teethare not developed. The three following legs are slender, unarmed,and terminate in a small simple curved claw. The uropoda reach alittle beyond the distal end of the terminal postabdominal segmenttheir bases are armed above with a spine ; the rami are ovate andciliated, the outer a little broader than the inner. Colour (in spirit)light yellowish. Length of the single specimen (a female) about10 lines (21 millim.), of second chelipede about 7 lines (15 millim.).The secojid. specimen was found in the interior of a shell of aspecies of Finna, obtained on the coral-reefs at Port Molle, andbears ova.This species in its general appearance and in many details, as inthe edentulous rostrum, ovate antennal scales, and the form of thechelipedes, bears a striking resemblance to Anchistia awantiaca,Dana*, from the Fijis, but differs in the form of the outer maxillipcdesand of the dactyli of the ambulatory legs, in which it ratherresembles Hcnjnlius. As this is the only spirit-specimen, I havenot ventured to dissect the buccal organs to ascertain the absenceof a mandibular palpus ; but there can, I think, be little doubt thatthis species is rightly placed with HarpUius and Anchistia.There is in the British-Museum collection a dried example fromShark Bay, \y. Australia {F. M. Rapier, H.M.S. Herald ' '), whichprobably belongs here. This specimen also was found in the interiorof a Pin?ia-shel\.Another closely allied species exists in the Museum collection,represented by a single dried specimen from the interior of Tridaena(H.3I.S. 'Herald'), without precise indication of locality, whichdiffers in the form of the rostrum (which appears acute in a lateralview), and in having a spine on the anterior margin of the carapace* U.S. Expl. Exp. xiii. Cr. i. p. 581, pi. sxxviii. fig. 2 (1852).