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

246 COLLECTIONS FROil MELANESIA.gascar {Rev. Deans Cowan) ; Mauritius (Lady F. Cole) ; Rodriguez{O. Gulliver); Indian Ocean, Celebes, Macassar, &c. (coll. Dr.Bleeker) ; Keeling Islands (Lieut. Burnahy, R.N.) ; various islandsof the Fiji group (H.M.S. Herald ' ') ; Samoa Islands, Upolu (Rev.S. J. Whitmee) ; Sandwich Islands ( U.S. Exploring Expedition andW. H. Pease) ; besides others without special or with insufficientlyauthenticated locality.All the Australian examples I have seen, with one exception,appear to belong to the variety (as at most I consider it) describedby Milne-Edwards as intermedins. One, however, of the specimensobtained at AVest Island (No. 149) must, on account of its coloration,be referred to the variety designated tlml-ujar by Owen. Thecolour is not indicative of geographical races or subspecies, since ofthis latter variety I have examined specimens both from the Mauritiusand the Sandwich Islands. Mr. Kingsley, in his recent"Synopsis of the Grapsidse,"* does not regard these forms even asvarieties, but unites them all under the one designation M. messor.90. Chasmagnathus (Paragrapsus) laevis, Dana.A male and female from Port Jackson, 0-7 fms. (one numbered104), are referred here. They differ somewhat from the New-Zealand examples which I suppose belong to this species, in theBritish-Museum collection, in having but very few or no yellowspots on the surface of the carapace. In the New-Zealand examples(SoiverJri/), and others without definite locality in the Museum collection,both carapace and legs are plentifully mottled with yellow,and the front is perhaps a trifle more rounded at its lateral angles ;but in other particulars the specimens are so nearly alike that I donot venture to regard them as belonging to distinct species.Mr. Kingsley, in his " Synopsis of the Grapsidte " above referred to(p. 222), has referred to the synonyms of this species. He unitesthe genera Chasmagnathus and Paragrapsus, and the distinctionsbetween the two are certainly very slight ; but it may be convenientto reserve the name Paragrapsus as a subgeneric designation, atleast, for the species with less convex body and broader less deflexedfront, which, in what may be regarded as the typical Chasmagnathi(e. g. C. convexus and C. gra^iulatus), resembles that of Helice tridensin being strongly curved downward, with an arcuated anteriormargin that does not project in the middle line over the antennularyregion.The range of C. Icevis, as far as at present ascertained, is restrictedto the north and south-eastern shores of Australia and the New-Zealand coasts.91. Sesarma l)idens, De Haan ?Port Curtis, 7-9 fms. (No. 85). Two specimens (males).These examples are referred with little hesitation to S. hidens,* Proc. Acad Nat. Hci. Philad. p. 190 (1880).