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Show 1899.] ASTRJEID CORALS FROM THE SOUTH PACIFIC. 747 1. GoNIASTRcEA EXIMIA Dana. Astrcea eximia, Dana, Zooph. p. 242, pl. xiii. fig. 4 (1848). Goniastrcea eximia, Milne-Edwards & Haime, Cor. ii. p. 448 (1857). The corallum of this species forms large irregularly-convex masses, which have thin spreading edges, covered underneath by a well-developed epitheca. Three orders of septa are complete, and the fourth nearly so. Of these, two orders typically have pali, forming a well-marked crown round the axial fossa. The number of pali, however, varies greatly, in some colonies averaging in the larger calices 10-11, and in others 12-13. Some, too, of the tertiary septa in the largest calices project to the axial fossa, and have distinct paliform lobes. There is a true, finely trabeculate columella, about 1 m m . broad, situated about 2 m m . below the pali, which themselves are about 1 ram. below the edge of the calice. The larger calices are 3-4*5 m m . in diameter. The walls are very thin, formed by two completely-fused thecae. The septa are scarcely exsert, and are not generally continuous from calice to calice. Usually the primary septa in one calice lie opposite to the tertiary or quaternary septa in a neighbouring calice, not opposite to primary or secondary septa. Rotuma; reef, three specimens. Wakaya, Fiji; reef, two specimens. 2. GONIASTRCEA SOLIDA Blainville. Dipsastrcea solida, Blainville, Diet. t. Ix. p. 338 (1830). Goniastrcea solida, Milne-Edwards & Haime, Cor. ii. p. 444 (1857). A single small specimen from the Rotuma reef, conforming closely to the above descriptions. Genus ASTRCEA. Astrea, Lamarck, Syst. des Anim. s. Vert. p. 371 (1801). Astrcea, Dana, Zooph. p. 200 (1818). Favia, Milne-Edwards & Haime, Cor. ii. p. 426 (1857). Astrcea, Quelch,' Challenger 'Report on Reef Corals, p. 96 (1886). Corals of this genus were among the most abundant found both at Funafuti and Rotuma. They do not occur generally near the rim of a reef, where it is exposed to the open sea, but are often found on the reef-flat behind. Their favourite position, however, is on shoals-preferably near a passage-in the comparatively quiet water of the lagoon. Milne-Edwards and Haime enumerate 44 species of the genus. Of these species Dana's descriptions are by far the best, as the main characters on which the species are based are always indicated and figures of all are given. Valenciennes's M S S . descriptions are absolutely useless; and many of the species described by |