1906.] ALCYONARIANS FROM ZANZIBAR. 425 



the stem ; the stem gives ofl' a large number of primary branches 

 which break up into secondaries and these bear the twigs with 

 umbels of polyps. The trunk and base are wanting. The spicviles 

 on the sui'face of the genei'al ccenenchyma are transparent near 

 the base and pale yellow higher up. Just below the polyp- bearing 

 twigs some of the yellow spicules show a red core, and there is 

 thus a gi'adual transition to the crimson-i'ed spicules of the polyp- 

 stalk, anthocodia, and tentacles. 



The polyps are arranged in small clusters of 7-10; and these 

 are again grouped into lai'gei- umbels. Though there is no 

 crowding, the polyps form a fairly continuous covering. A polyp is 

 usually about 1'5 mm. in length and is covered by longitudinally 

 disposed spindles. Three large ones form a strong Stiitzblindel 

 which projects beyond the anthocodia for about 1 mm. The 

 anthocodia stands almost at right angles to the polyp-stalk, and is 

 supported by red spindles in 8 double I'ows, about 7 paii's in each 

 row. A distinctive feature is that the topmost spicules of each 

 double row project in triangular points beyond the bases of the 

 tentacles. The tentacles are white, but bear numerous small red 

 spicules aiTanged transversely, so that a fine tentacular opeiculum 

 is formed over the contracted polyp. 



The spicules are spindles with fine warts or short blunt spines, 

 and show a great range of colom*. Some are red, some are yellow, 

 some ai'e combinations of these colours, and others are transparent. 



The lai^gest are those of the Stiitzblindel, about 4 mm. in length 

 by 0"2 in breadth, and some of those on the polyp-stalk are about 

 3"5 mm. in length. Those of the general surface of the 

 coenenchyma are : 2x0'15mm.; 1-8 x 0*15; I'SxO'l; 1-35 xO°l; 

 0-8 X 0-1; 0-35 X 0-04 ; 0-3 x 0-03. 



The red spicules of the anthocodise are mostly about 0"6 x 0'04 ; 

 a projecting one had a length of 1*2 x 0'06. 



Locality. Wasin. 



Stereonephthya zanzibarensis, sp. n. (Plate XXXI. figs. 3 

 & 4.) 



A small but complete colony of a yellowish tint, 10 mm. in 

 height and 8'5 in breadth. The trunk of the colony is limp, but 

 the main polyp-beai'ing pai-t is stiff" and brittle. The polyps have 

 short stalks about 1 mm. in length ; some arise from the trunk, 

 but most are borne on the branches. They occur close together, 

 but are not united into bundles. The anthocodia stands at right 

 angles to the stalk and has its oral opening directed towards the 

 branch. The Stiitzblindel has one main projecting spicule 

 (l"2xO"125 mm.) supported by 2 or 3 bent spindles on either 

 side ; below these there are a few in the direct line of the 

 projecting spicule, passing continuously into the superficial spicules 

 of the coenenchyma (0'6, 0*4, and 0*25 mm. in length). On the 

 anthocodise there are eight double rows of spindles, each row 

 consisting of 1 5-20. The opposite members of a double row slope 

 towards one another at an acute angle, which widens towards the 



