CORALS FROM SOUTH AFRICA, 879 



the degree of extension, but the apices of the tentacles are never 

 seen to any extent. 



In all the better expanded polyps, the crown of spindles is very 

 apparent. This crown has frequently a reddish or brownish 

 coloration. The general surface of the colony has a greyish 

 colour, which is produced by the spicules. 



Owing to the varying degree of extension, the polyps naturally 

 vary considerably in size, 



The verrucas have minvite lobes, measuring as much as 2 mm. 

 in height and 1'6 mm. in diameter. 



The ccenenchyma is thin at all parts and aometimes is 1 mm. in 

 thickness. 



The axis of the secondary branches varies in diameter, from 

 about 1'3 mm. in the lower branches to 1 mm. in the apical 

 branches. 



The interval between the polyps varies from about '1 mm. 

 to r9 mm. There is a terminal polyp at the apices of the 

 branches. 



The spicules of the crown of the polyp are straight or curved 

 spindles, armed with blunt tubercles. The majority of the 

 spindles ai-e very mvich curved, but a few are straight. The 

 tubercles have a tendency to great irregularity of shape, and 

 vary very considerably. The spicules from this part also vary 

 notably in shape, some being rod -like, others club-like, but 

 there are all transitions between the different forms. The 

 number of tubercles or spines also vaiies considerably, in some 

 spicules there are scarcely any, in others they are numerous. In 

 some of the more curved spindles there is a secondary offshoot 

 fi'Oin the main axis about the middle of its length. 



The spicules of the lower part of the polyp differ, as a rule, in 

 shape from those of the upper crown. Many of the spicules from 

 this part are ^^Blattkeulen,'' others are more of the form termed by 

 Kolliker " Kalkkorper.'^ There is much variety in the shape of 

 those spicules, probably every stage giading the one into the 

 other. There are also a few spicules similar to those occui-ring in 

 the crown of the polyp, namely curved spindles. There are other 

 spicules which may be more appropriately termed spinous clubs. 



The su]3erficial spicules of the ccenenchyma are much smaller 

 than those of the polyp. They are mostly small " Ecdkkorper " 

 with irregvilar blunt processes coming off' in all directions, less 

 fi'equently there are short spindles with broad processes. 



The dimensions of the spicules are as follows : — iSpindles of the 

 polyp crown, from 0-102 x 0-017 to 0'340 x 0-085 mm.; '' matt- 

 keulen" of the lower polyp, from 0-17 x 0-119 to 0-289 x 0-085 mm. ; 

 '' Kalkkoyyer" of the lower polyp, from 0-153x0-119 to 0-204 x 

 0-153 mm. ; " Kalkkorper " of the ccenenchyma, from 0-047 X 0-030 

 to 0'105 X 0-076 mm. ; spindles of the ccenenchyma, from 0-030 x 

 0-023 to 0-088 xO-061 mm. 



There was unfortunately no label attached to this specimen, 

 and thus the exact locality cannot be stated. 



