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Show 1906.] ALCYONARIANS F R O M ZANZIBAR. 435 The tentacles were measured in two specimens and were found to vary from 2*95-3 m m . in length. The surface spicules (0*5x0*05) are longer than the spicules of any of the other specimens. The axial polyps vary from 57-59 m m . in length and from 1*2-1*3 m m . in diameter. The average length of the lateral polyps is 4 m m. The axial polyp treated with boiling caustic potash showed a firm compact tube marked by longitudinal ridges, and formed of t,Avo layers of spicules, an outer layer of stouter spicules, an inner of more slender forms. Locality. Wasin, 10 fathoms. In another specimen there is a rhizoid-like attachment. The primary axial polyp has been broken, but it is still 67 m m . in length. The complete secondary axial polyps are 95 m m . and 72 m m . in length. The lateral polyps are arranged irregularly on the axial polyps. On the lower part of the secondary axials they are 3 m m . by 3 mm., wThile on the upper part they are 2*6-3 m m . by 1*6 m m. The axial polyp treated with boiling caustic potash shows a coherent tubular axis formed of two layers of spicules, an outer layer of stouter spicules with more prominent spines and an inner of longer, more slender spicules with few spines. Locality. Wasin, 10 fathoms. In another specimen the colour was light brown, the lateral polyps were about 3 m m . in length, and the longitudinal grooves were much less marked than in those above described. The spicules are transparent spindles with long, irregular, sometimes branching spines. The following measurements were taken of length and breadth in millims.:-0*12x0*04; 0*14x0*05; 0*18x0*05; 0*2x0*06. Locality. Kokotoni Harbour, Zanzibar West, 5 fathoms ; Wasin Channel, 10 fathoms. Previously recorded from Arafura Sea, 49 fathoms. Family C G E L O G O R G T I D ^ :. CCELOGORGIA PALMOSA Wright k Studer. A number of fragments which are evidently the portions of a large colony. In some of the larger fragments the axial polyp of the first (?) order attains a diameter of 5 m m. The specimen agrees closely with the description given by Wright k Studer, except that in the tentacles, which are short and stumpy, there are four rows of pinnules on the oral surface, and in the outer row there are usually ten pinnules, not eight as stated in the ' Challenger' Report. The colour of the colony when preserved in spirit is a very pale green, but when dried it is almost white. The green colouring-matter is very soluble in spirit. The present specimen also shows a greater degree of elasticity than that ascribed to the 'Challenger' specimen; when dried, however, it is very brittle and hard. PROC. ZOOL. Soc-1906, VOL. I. No. XXIX. 29 |