126 CLASS II.— ORDER II. 



est rose to a dull brown, or greenish, or only with 

 a tinge of red. Infinite gradations are observed: but 

 they all bleach by the action of the atmospheric fluids. 



The Polypidoms of this genus are found in all la- 

 titudes, in all depths, and on all the coasts of the five 

 divisions of the world. They are however observed to 

 be larger in the equatorial seas, more brilliant in their 

 hues, and more elegant in their form. Fixed usually 

 on rocks, or other hard and almost immovable bo- 

 dies, they resist the influence of the waves, and are 

 very rarely cast upon the shores. Only one or two 

 species of Corallinas are parasites on the Tha- 

 lassiophytes, whilst nearly the whole of the Janias 

 are found upon these vegetables. 



The Corallinas vary but little in their height; they 

 sometimes exceed a decimetre, but are in general 

 less : I however never met with any under two centi- 

 metres. 



The Corallina Officinalis was formerly used as an 

 anthelminthic, or destroyer of worms, and absorbent ; 

 but in the beginning of the eighteenth century it 

 seemed nearly to have fallen into disuse : at a later 

 period it vvas again brought into vogue from the re- 

 putation of the Fucus Helminthochorton, vulgarly 

 called Moss of Corsica, whose properties seem to be 

 of the same nature. 



A very good analysis of the Corallina Officinalis, 

 such as it is found in the shops and in collections, has 

 been given by M. Bouvier of Marseilles : he found the 

 component parts of a thousand grains to be — 



