404 TROF. J. A. THOMSON AND MR. W. D. HENDERSON ON [Apr. 10, 



somewhat different, and no rods are present unless the side view 

 of the discs could be called rods. 



In another set of specimens veiy like those mentioned above 

 the polyps vary from 3'6 5 mm. in length. They are marked by 

 annulations and sometimes by longitudinal lines. The tentacles 

 are shoi't, but the pinnules are arranged in three rows. The 

 spicules are small discs O'Ol mm. in diametei-, somewhat pitted in 

 appearance. 



Locality. Zanzibar shore. Pieviously from Zanzibar, Red Sea. 



Clavularia margaritifer.^ Thomson & Henderson. 



Numerous stift' white poly}is lise at right angles to a height of 

 6-7 mm. from narrow stolons (0-3 0-4 mm. across) spreading 

 over a flattened twig. The strands of the stolon ma)' form a 

 network, but never coalesce into a membrane. The specimens 

 agree closely with C. margaritiferfe, e. g. in the alnnidance of 

 interlocked capstan-like spicules (double clubs and double wheels), 

 0-04-0-07 by 0-02-0-04, with three or four large tubercles at 

 each end, in being broader orally than basally (O'G at the base, 

 1-1*3 mm. distally), in being often broader than the stolon. A 

 small portion of the upper end of the polyp is capable of 

 invagination along with the tentacles ; the expanded tentacles are 

 seen in a few forms as if rising on a naiiowei- neck from within 

 a broader funnel. There is thus the l)eginning of an interesting 

 distinction between a calycine portion and an anthocodial portion 

 which are separated by a slight consti'iction. This points on to 

 fStpupodiiim. There is a single row of 8 or 9 short pinnules on 

 each side of the tentacles ; they are about O'l mm. in length. 



The specimen difteis from that described as 0. maryaritiferce 

 in having no spicules on the tentacles. The rest of the surface 

 has a granular appearance due to the spicules. 



Locality. Chuaka. 



Previously recorded from Gulf of Maiiaar. 



Clavularia crosslandi, sp. n. (Plate XXX. fig. 6.) 



The stolon is a, membranous plate. The general coloui' is light 

 brown. 



The polyps ai-e long and slender, the walls deeply marked by 

 longitudinal narrow grooves a.nd broad white iddges. The length 

 of tlie polyps is about 5 mm., the bi'eadth about 0'75. The 

 tentacles are 2"5-3 mm. in length. Many of the polyps have a 

 swelling just 1 )elow the insertion of the tentacles, 1 "2 mm. in width. 



The tentacles are flat and lanceolate, with the pinnules arranged 

 in two rows, but this appearance may be due to the crowding of 

 the pinnules of one row. They leave a bare space on the oral as 

 well as on the aboral surface of the tentacles. Tlie pinnules are 

 very short and bluntly conical, thereby differing very markedly 

 from G. garcice, which the colour and the longitudinal grooves at 

 first suggested. There ai-e several noteworthy features in regard 



