retroflexed insertion of the branches, noticed by Sonder, is not 

 more striking in this plant than in large, deep-water specimens 

 of T, vulgaris. Indeed, except in the slenderness of all parts, 

 and in the sub-distant and laxly inserted leaf-vesicles, I find no 

 absolute distinctive characters. 



The T. vulgaris has not yet been recorded as Australian, but 

 it probably will be found on the northern or north-western 

 coasts, or on the great coral reefs of the north-east. Our T. 

 gracilis seems to be very rare. I am indebted to Herr Binder, 

 Biirgermeister of Hamburg, for the specimen here figured, 

 which is larger and in better condition than earlier specimens 

 given to me by Dr. Lemann. Mr. Clifton has not as yet sent 

 this plant. 



Fig. 1. TuKBlNARiA GRACILIS, — the natural size. 2. One of the lecif-vesicles, 

 bearing a tuft of fruit, on its pedicel : — magnified. 



