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Show 1899.] ASTRcEID CORALS FROM THE SOUTH PACIFIC 749 polyps similarly coloured. The larger calices are 9-14 mm. in diameter by 5-7 m m . in depth. The dividing-walls vary from 1*5 to 2*5 m m . in breadth, and have always a well-defined sulcus. The septa form three complete orders, and there are sometimes a few septa of a fourth cycle. The primaries and secondaries are equal in size, about 2 m m . exsert, and have well-marked paliform lobes. By the fusion of trabeculae from their septal edges, a well-defined oval columella is formed. The under surfaces of both specimens are covered by a distinct thin epitheca. Rotuma; reef-flat and rim of reef. The specimen from the reef-flat has its calices broader and shallower than the one from the rim. The paliform lobes in the same specimen are also much more distinct and form a marked crown round the columella, which is generally at least 2 m m . in diameter. 4. ASTRCEA OKENI Milne-Edwards & Haime. (Plate XL VII. %• 2.) Favia okeni, Milne-Edwards & Haime, Cor. ii. p. 430 (1857). This species differs from the preceding in having broad dividing walls (2*5-4 mm.) between its calices with very distinct sulci. The corallites do not have any distinct raised rim, save that which is formed by the nearly equally exsert upper ends of the septa, of which there are three complete cycles. All the septa fuse with the columella, the tertiaries a little lower than the primaries and secondaries. All have distinct, bluntly angular teeth at their lower ends, but these do not in any way simulate pali. (Pl. X L VII. fig. 2.) Rotuma; boat-channel. 5. ASTRcEA PUTEOLINA Dana. Astrcea puteolina, Dana, Zooph. p. 223, pl. xi. fig. 3 (1848). A single flattened mass, the incrusting base of which has been eroded away. The mass is much incrusted by nullipores; when obtained, only the calices round the edges were alive. The specimen differs from those of A. fragilis in the collection in having larger calices, 11-13 m m . iu diameter by 4*5-6*5 m m . in depth. There are three complete cycles of septa, of which two reach the columella. The walls are about 2 m m . thick, and the septa of neighbouring calices are often continuous over them, the sulcus being scarcely noticeable. The species is almost exactly an enlarged edition of A. fragilis, but the septa and corallum, even in the smallest calices (7 m m . in diameter), are much more massive. Funafuti; lagoon shoals. 6. ASTRCEA L O B A T A Milne-Edwards & Haime. Favia lobata, Milne-Edwards & Haime, Cor. ii. p. 434 (1857). Favia lobata, Klunzinger, Die Korall. des R. Meeres, iii. p. 31, pl. iii. fig. 9 (1879). T w o specimens, which conform closely to the above descriptions, and to some extent show the same features as the two specimens |