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Show 1906.] ALCYONARIANS FROM ZANZIBAR. 401 The beginning of a differentation of calyx and anthocodia in C. margaritiferm may be regarded as a hint of the Sympodium type; the slight union of the bases of the polyps in G. mollis m ay perhaps be regarded as pointing towards the Xenia type. CLAVULARIA GARCLE Hickson. Several specimens appear to be referable to this species, if its diagnosis is made rather more elastic. The polyps are 10-13 m m . in length, with thin transparent walls, and show no sign of being able to contract. Mr. Crossland states that the living forms had very mobile tentacles opening and closing regularly. The tentacles are from 6-8 m m . in length and have the pinnules arranged so as to leave a wide bare space on the oral and a narrower bare space on the aboral surface. The long pinnules are in one row and they vary in number from 16 to 30 on each side. There is occasional simulation of two rows. The fact that the pinnules vary from 16-30 pairs shows that the number of pinnules is not in itself a character of much diagnostic importance. Minute, slightly roughened, rod-shaped spicules are abundant throughout the colony and give it a peculiar glistening appearance; they are from 0*04-0*05 m m . in length and 0*007 m m . in breadth. Hickson describes the spicules of G. garcice as scattered and not crowded ; they are here densely crowded. Locality. Chuaka, E. Zanzibar. Previously from Chagos Archipelago. In another group of polyps, which we are inclined to refer to the same species, there are some interesting differences. The bodies of the polyps are more substantial, but they are more contracted (5*4 m m . in length). The tentacles are about 4 m m . in length, and while some show two rows of pinnules with perfect clearness, others show three rows equally distinct. The number of pinnules in a row varies from 12-15. In the body of the polyp and on the tentacles the spicules are closely packed, thus giving a granular glistening appearance to the polyp. The spicules are 0*05 m m . in length, and seem to be identical with those above described. Locality. Wasin, British East Africa. CLAVULARIA GARCLE Hickson, var. INERMIS, nov. The polyps, which rise from a membranous stolon to a height of 9 mm., are marked by annulations and also by longitudinal lines. The tentacles are long and pointed, from 3-3*5 m m . in length by 0'8 m m . in breadth at their proximal end. The pinnules are arranged in three rows on each side, in the outer row they may vary from 19-23 in number. They leave a free space on both the oral and the aboral surface. In some polyps we found no trace of spicules; in others we found a few small rods. There are crowded zoochlorellaa. |