54 CLASS I.— ORDER I. 



ELZARINA. 



Frondescent Polypidoms ; dichotomous, cylin- 

 drical, and not articulated. Cells large and dispersed, 

 scarcely projecting ; openings oval. 



The only species comprised in this genus resem- 

 bles a small cylindrical fucus, branching or dichoto- 

 mous. 



The substance is nearly membranous. Colour brown, 

 more or less dark. 



They never exceed four centimetres in height ; the 

 diameter of the branches varies from one to two mil- 

 limetres ; the higher ones are sometimes in the form of 

 clubs. 



Elzarina BlairwilUi. Cells membranous, large 

 and dispersed. — Plate 2. fig. 3. a. B. 



On the Thalassiophytes of Australasia and of the 

 isle of Timor. 



CELL ARIA. 



Plant-like Polypidom, cartilaginous, stony, cy- 

 lindrical, and branching. Cells dispersed on the whole 

 surface. 



The Cellarias are always articulated, cylindrical, 

 dichotomous or branhcing; covered with dispersed 

 cells, having a large polygonal opening. Their sub- 

 stance is almost wholly calcareous, which renders 

 them very fragile and very little flexible. 



When first taken from the sea, their colour is some- 



