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Show 1899.] ASTRcEID CORALS FROM THE SOUTH PACIFIC. 753 edges of all are rough without any distinct teeth. The columella is formed by very fine trabeculae from the edges of the primary septa, and in the largest calices is usually about 1 ram. across. The endotheca forms transverse partitions-distant about *5 m m . from one another-across the interseptal loculi. Funafuti. 3. ORBICELLA WAKAYANA, n. sp. (Plate XLIX. fig. 2.) There are three specimens, which agree very closely with 0. annuligera in its described characters, but have their calices seldom less than 3*5 m m . deep. They may possibly be identical with that species ; but as m y specimens have uniformly deep calices, with other corresponding differences, I have no option but to describe them as a new species. The colonies form spreading and incrusting masses covered uniformly underneath by a distinct epitheca. The calices are round, and commonly 5-6 m m . in diameter by 3-4*5 m m . deep. They usually have a quite distinct rim, often as much as 2 m m . high, and are commonly about 2*5 m m . distant one from another. The septa are 30-40 in number and cannot be divided into cycles. They are generally equally exsert, but usually about half reach the columella, while half are very narrow. A certain number of septa (6-10) are often somewhat broader at their upper ends and so may simulate a primary cycle. The costae are sub-equal, and are not, except where budding has recently taken place, continuous between the calices, which are joined solely by exothecal trabeculae. The septal edges are very finely spined, and the larger septa in some calices merge directly into the columella, but in others may have each a distinct, fine, paliform tooth, with its summit even 2 m m . above the columella. The latter is generally almost round, 1-2 m m . in diameter, and is formed by very fine, closely anastomosing trabeculae from the septal edges. In section, the thecae of neighbouring calices are seen to be quite distinct one from another, the exotheca forming fine trabeculae, never filling up the intertbecal spaces. The interseptal loculi are deep-7-8 m m . - a n d closed in below by thin, nearly horizontal endothecal dissepiments, distant about 1 m m . one from another. Wakaya, Fiji; three small specimens, all obtained close to the edge of the reef. 4. ORBICELLA TERSLPORA Lamarck. Astrea versipora, Lamarck, Hist, des Anim. s. Vert. ii. p. 264 (1816). Plesiastrcea versipora, Milne-Edwards & Haime, Cor. ii. p. 490, pl. D 7. fig. 5 (1857). A single specimen, closely resembling the above descriptions and a specimen so named in the British Museum. The species possesses well-marked crateriform calices, with free edges, joined only by |