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

CKTJSTACEA, 287which is distingiiished hy having a small but well-developed spinuleon the outer side of the antennal scale at base, and the fingers ofthe smaller chelipede slender, arcuated, considerably longer thanthe palm, thickly clothed with long hair on their inner margins, andhaving between them an interspace when closed. In the adult thefingers are sometimes elongated to a remarkable degree, three timesas long as the palm in one specimen. This form I propose todesignate Alplwus rjracilidigitus.C'nmgon monopodium^ Bosc *, is very possibly this or an alliedspecies. As, however, it is impossible to identify that author's briefdescription and rude figiire as given in his second edition (1830) withany species with certainty, and as his designation has never beenadopted by any subsequent writer, I prefer to retain Audouin's nameA. edwarclsii, about which there is no uncertainty and which hasbeen used by several authors of repute. I have never seen the firstedition of Bosc's work.Both the Alplieus edwardsii, as described by Dana from Cape-Verd specimens, and the yi. pacificus, Dana, from the SandwichIslands, diff'er in having the second joint of the carpus of the secondpair of legs much shorter than the first joint, but are probably merevarieties of the typical A. edtvardsii.The species I described from the Samoa Islands as A. lineifer f isallied to A edwardsii, biit may be distinguished by the smootherchelipede and the existence of a well-developed spine on the outerside of the peduncles of the antennae. It may perhaps be the youngoi Alpheus imrvirostris, Dana, from the Balabac Straits ; but the firstjoint of the carpus of the second pair of logs is relatively shorter,and the large chela of the first pair relatively narrower and moreelongated than in Dana's figure.6. Alplieus ohesomanus, Dana.A small example from Port Molle, 5-12 fms. (No. 118), is referredto this species.Several small specimens are in the British-Museum collection fromOvalau, Fijis {H.M.S. ^Herald'). Dana's types were also from theFiji Islands. Dr. F. Eichters has recently recorded this speciesfrom the Mauritius (Isle des Fouquets).This species is remarkable on account of the turgid form of thelarger chelipede and the great elongation of the second carpal jointof the second pair of legs.7. Alplieus gracilipes, Stimpson.I thus designate a specimen from Port Molle, obtained on thebeach (No. U5), and another small example from Flinders Island,* Hist. Nat. Crust, ii. p. %, pi. xiii. fig. 2 (180l')-t Ann. & Mag. Nat. Hist. ser. 4, xvi. p. 343 (1875).