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Show 1906.] ALCYONARIANS FROM ZANZIBAR. . 415 a flattened surface, and looks very like a Glavularia or a Sym-poclium in the arrangements of the polyps on the upper surface. The principal stalk soon divides into two branches, each of which divides several times and bears the polyps. The polyps are about 5 m m . in length, and slightly under 1 m m . in breadth, and have bushy heads, caused by the featherlike tentacles. The latter are about 3 m m . in length. The pinnules are arranged in one row (15-18) on each side, thus leaving on both the oral and the aboral surface a free space which runs the whole length of the tentacle. The pinnules are long and slender, often about 1 m m . in length by 0*1 m m . in diameter at the base and 0*05 m m . in diameter at the tip. Although this specimen differs from (1) in colour (when living) and in mode of branching, the polyps are closely alike. Loccdity. Off the Zanzibar coast, a few miles south of the town ; 5 fathoms. Previously recorded from Zanzibar and Kokotoni. (3) A third specimen was described in the living state as having " a pink body with blue-green zooids " ; when preserved it had a clear white colour. The base is formed by the end of the stalk growing round a piece of coral. The stalk is firm in texture, dividing at a little distance above the base into three main branches, each of which divides and re-divides into the polyp-bearing portions. The polyps measure 3*5-4*5 m m . in length with an average diameter of nearly 0*1 m m . The tentacles often appear blunt and short, but this is merely the contracted condition, as other parts of the colony show. Sixteen contracted pinnules were counted on each side. Loccdity. Kiungani, near Zanzibar town ; lowest tide. It may be of use to emphasize the point that these three specimens presented when living somewhat different coloration :-- (1) " A brilliant sea-green colour, except the upper faces of the small zooids, which are brown " ; (2) " pink stems with slender brown zooids " ; (3) " pink body with blue-green zooids." May's specimens were " flesh-coloured with a tinge of bright blue." This may be enough to show that the natural colours of Cespitularia are of little specific moment. (4) In a fourth specimen the lower end of the stalk spreads over a piece of calcareous conglomerate. The stalk is firm and marked by longitudinal ridges and grooves; it divides into branches, which at some parts bear the polyps themselves, and at others divide into small polyp-bearing branches. The polyps are, on an average, 3*5 m m . in length by 1 m m . in breadth. On the tentacles, which are 1*5 m m . in length, the small pinnules (0*04- 0045 in length) are arranged in one row on either side of the middle line, thus leaving on the aboral surface a broad, and on the oral a narrow free space which stretches the whole length of the tentacle. |