TURBINARLE VAEIE CONTOKT^. 75 



In the above description I have assumed that the central conical cavity is the original 

 cup. This assumption is quite warrantable, and, indeed, almost necessitated by the present 

 state of our knowledge of the development of the Turbinarian stocks. The only doubt which 

 rises in my mind as to whether this is actually the original cup or a secondary cup formed by 

 a fold of an earlier stock, is due to the complete disguising of the stalk. This, however, is 

 hardly to be wondered at. When the process began, the stalk would be comparatively thin. 

 The necessary thickening which would accompany such luxuriant growth, would adapt itself 

 to the needs of that growth, and the primitive stalk would, it seems to me, soon be completely 



lost. 



C Commissioners, Chinese Court, International ) 

 a. South Chinese Seas. \ j,.^^^^.^^ Exhibition of 1883. \ ^^^^'^ 



Species 58. Turbinaria subversa. (PI. XXV. ; PI. XXXIII. fig. 6.) 



Description. — CoraUum a nodulated mass, with thin margin much contorted, drooping 

 round the stalk, which has completely enveloped a loose mass of extraneous matter. The 

 stock is thus free, but weighted by the fragment of the substratum enclosed in its stalk. 



Calicles sparse, short, thick protuberances, often only the thick margins project. Aper- 

 ture smaller than the top of the protuberance, oval, regular, 2 • 5 mm. long diameter. Septa 

 thick, very variable (15 to 28), not equal, projecting to or beyond the half-radius circle, 

 bending round rather sharply to descend perpendicularly round a distinct oval fossa of 

 medium depth. Columella distinct, oval or straight, coarsely granular, protuberant. Inter- 

 septal loculi according to the number of septa developed, distinct, or very thin and slit-like, not 

 bounded peripherally but continuous with the furrows of the ccenenchyma. 



Coenenchyma iinely echinulate, with a furry appearance. 



It is impossible to say whether this is an abnormal or a normal specimen. The young 

 cup was apparently attached to some loose fragment of the substratum, and in course of time 

 rolled over on its side. The stalk grew round the mass, which thus acted as an anchor. This 

 appears to be purely accidental. Yet it may have become normal to a species flourishing in a 

 locality where the substratum largely consists of loose fragments. The characters of the 

 calicles are peculiar, and until we possess fixed stocks showing the same calicles, we must 

 regard this specimen provisionally as representative of a type. On the other hand, again, it 

 must not be forgotten that the change in position due to rolling over, might seriously modify 

 the general characters of the calicles. But as we have no light to guide us in estimating the 

 influence of such change of position, we must be content with provisionally labelling the 

 specimen as representing a new type. 



a. Palm Island, Great Barrier Keef. Sa\dlle-Kent CoU. (Type.) 



