Simpson — A Revision of the Gorgonellidae. 97 



bare strips which become more indistinct, but still visible, towards the tip 

 (fig. 73). These are spirally twisted ; but this is, no doubt, due to a general 

 torsion of the colony. In each series the polyps appear in rows diverging 

 from the bare tracts ; this gi\'es a very marked spiral arrangement, but this 

 is also due to torsion. Transversely four or five is a common number in each 

 series. The verrucae are sub-cylindrical and closely adpressed to the stem; 

 the outer insertion is lower than the inner. They arc about 1-5 mm. in 

 height and 0-75 mm. in diameter at the base. When retracted they are sub- 

 conical, and have eigl),t converging lips (fig. 74). 



The canal system is very definite and typical ; the two main longitudinal 

 canals are extremely large. 



The axis is yellow in colour, and markedly calcareous; the surface is 

 apparently smooth ; it tapers only slightly in the portion preserved. 



Locality. — Off Table Island, Cocos Group, Andamans, 15-35 fathoms. 



When we take into consideration the fact that the great majority of 

 these forms are fragmentary, and also the slight basis on which the genera 

 Juncella, Scirpearia, and Scirpearella were formerly dillerentiated, there is 

 small cause for wonder that the various specimens were referred to one or 

 other of these genera on account of differences which we hope to show are 

 not specific, but only different manifestations assumed by extremely plastic 

 organisms. 



We have made a very exhaustive study of the spicules in all the forms of 

 which descriptions have been given ; and although these show certain deviations, 

 nevertheless they may be grouped into a number of more or less definite 

 types. 



Fig. 75 gives a very good representation of the difterent tyjies and 

 deviations therefrom in the case of the spicules in the Indian Museum 

 specimen. Fig. 72 of the spicules of Hickson's Juncc/la clongata has also 

 been added, and a comparison of these two groups should at once indicate the 

 affinities of the.se two apparently different forms. A similar comparison 

 might be made with regard to the others with a like result. 



If, then, the character of spiculation can be regarded as specific, we should 

 be compelled to unite all these extremely divergent forms into one very 

 variable .species. This procedure may, at first sight, seem rather drastic, as, 

 it may be argued, the dillerent variations occurred not in each specimen but 

 in different specimens. 



They distinctly show a range of variation which cannot be easily com- 

 prehended within an individual colony. 



We are, however, fortunately in the possession of a large colony wliieli 

 has the same characteristic spiculation, and which does actually show a range 







