91 



colours has been made in the description I have read of the 

 other species of Cavernularia, and the specimens I have had 

 the opportunity of examining have all been perfectly white, 

 with the exception of one specimen in the British Museum 

 and the specimens from the Cape described below. 



Specimen B. 



A smaller specimen obtained in the trawl off Robben Island 

 has a very different appearance. It is much more contracted 

 and wrinkled on the surface. It has none of the pinkish 

 colour noticed in Specimen A, and when cut with a knife 

 seems to be much tougher in consistency. A superficial 

 examination would suggest that this specimen belongs to a 

 different species to Specimen A, but the spicules present the 

 same characters, there is no trace of an axis, and the septa are 

 arranged in a corresponding manner in 'the two specimens. 

 This specimen, indeed, presents no characters except possibly 

 the proportional length of the rachis, which cannot be 

 accounted for on the supposition that it is very much con- 

 tracted. 



The measurements are of 



On comparing this specimen with the description of 

 Cavernularia elegans (Herklots) from Japan, it will be noticed 

 that the proportions are almost identical, and there can be no 

 doubt that it belongs to the same species. The only question 

 that is open to doubt is whether our specimens A and B 

 belong to the same species, and, as I have just pointed out, 

 the only character of importance in which they differ from 

 one another is the proportional length of the rachis. It is 

 a well-known fact that the stalk of some Pennatulids is 

 capable of very considerable changes in length and breadth 

 during life ; we know that the rachis of some Pennatulids 

 shrivels very considerably when brought on to the deck from 



