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Show 404 PROF. J. A. THOMSON AND MR. W. D. HENDERSON ON [Apr. 10, somewhat different, and no rods are present unless the side view of the discs could be called rods. In another set of specimens very like those mentioned above the polyps vary from 3*6-5 m m . in length. They are marked by annulations and sometimes by longitudinal lines. The tentacles are short, but the pinnules are arranged in three rows. The spicules are small discs 0*01 m m . in diameter, somewhat pitted in appearance. Locality. Zanzibar shore. Previously from Zanzibar, Bed Sea, CLAVULARIA MARGARITIFER,E Thomson k Henderson. Numerous stiff white polyps rise at right angles to a height of 6-7 m m . from narrow stolons (0*3-0*4 m m . across) spreading over a flattened twig. The strands of the stolon may form a network, but never coalesce into a membrane. The specimens agree closely with C. ma/rgaritiferai, e. g. in the abundance of interlocked capstan-like spicules (double clubs and double wheels), 0*04-0*07 by 0*02-0*04, with three or four large tubercles at each end, in being broader orally than basally (0*6 at the base, 1-1*3 m m . distally), in being often broader than the stolon. A small portion of the upper end of the polyp is capable of invagination along with the tentacles; the expanded tentacles are seen in a few forms as if rising on a narrower neck from within a broader funnel. There is thus the beginning of an interesting distinction between a calycine portion and an anthocodial portion which are separated by a slight constriction. This points on to Sympodium. There is a single row of 8 or 9 short pinnules on each side of the tentacles ; they are about 0*1 m m . in length. The specimen differs from that described as G. margaritiferce in having no spicules on the tentacles. The rest of the surface has a granular appearance due to the spicules. Locality. Chuaka, Previously recorded from Gulf of Mannar. CLAVULARIA CROSSLANDI, sp. n. (Plate XXX. fig. 6.) The stolon is a membranous plate. The general colour is light brown. The polyps are long and slender, the walls deeply marked by longitudinal narrow grooves and broad white ridges. The length of the polyps is about 5 mm., the breadth about 0*75. The tentacles are 2*5-3 m m . in length. Many of the polyps have a swelling just below the insertion of the tentacles, 1*2 m m . in width. The tentacles are flat and lanceolate, with the pinnules arranged in two rows, but this appearance may be due to the crowding of the pinnules of one row. They leave a bare space on the oral as well as on the aboral surface of the tentacles. The pinnules are very short and bluntly conical, thereby differing very markedly from G. garcice, which the colour and the longitudinal grooves at first suggested. There are several noteworthy features in regard |