1906.] ALOYONARIANS FROM ZANZIBAR. 405 



to the spicules : — (a) they occur in crowds on the ridges and give 

 these their white coloui-, and ai'e also continued up the backs 

 of the tentacles ; (6) they are irregular ovals like water- worn 

 sand-grains ; and (c) they are exceedingly minute, 0"01-0"02 in 

 length by 0-005-0-01 in breadth. 



Locality. Zanzibar Channel, low water. 



Clavularia repens, sp. n. 



This colony was found growing along with Hydroids on 

 submerged stems of the marine phanerogram before mentioned. 

 Its colour when living was reddish with brown polyps. The 

 stolon consists of narrow strands. 



The polyps are from 4*5-5 mm. in length, with an oral diameter 

 of O'9-l mm. They are narrower at the base. 



The tentacles are very short, only 0*4 mm. in length, with 

 short pinnules arranged in one roAv on each side of the middle 

 line. Each row consists of about 8 pinnules, and the two rows 

 leave a very wide bare space on the aboral and a slightly narrower 

 space on the oral surface of the tentacle. 



The specimen bears a strong supei'ficial resemblance to G. 

 mcm^garitiferce Thomson & Henderson, but the spicules are entirely 

 different. Here they consist of a continuous sheet of minute 

 capstans (aboutO'03-0"05mm. in height and about0'02 in breadth). 

 There are also some quadrangular foi'ms with an axial cross 

 (0-05 X 0-05). 



Localiiy. Common in Chuaka Bay. 



Clavularia pulchea, sp. n. 



A membranous plate gives origin to numerous long polyps 

 (23*5 X 3 mm.) with thin transparent walls. The tentacles, 9 mm. 

 in length, are transparent and feathery, with the pinnules 

 arranged in three rows on each side of the middle line, leaving a 

 bare strip on the oral and also on the aboral sm-face The 

 pinnules are long, cylindrical, and incurved, about 1"5 mm. in 

 length, usually 30 in a row. There are a few minute rod-like 

 spicules 0"05 mm. in length and 0*007 mm. in breadth. The colour 

 in spirit is white. 



In some respects this species approaches C celehensis Hickson, 

 e. g. in the large number of the pinnules, and in the long polyps 

 and tentacles. It differs in having a membranous stolon (as in 

 May's specimen), crowded, polyps, thin polyp- walls [cf. May, 

 p. 44), much more substantial pinnules, and distinct spicules. 



In another specimen it is worthy of note that the pinnules ai-e 

 found in all stages of retraction, from 2 mm. in length to small 

 wart-like projections. 



Locality. Zanzibar shore. 



Clavularia zanzibarensis, sp. n. 



A dense crowd of short polyps arises from an irregular mem- 

 brane spreading on nullipores. We have been unable to refer it 



27* 



