224 THE MARINE BOTANIST. 



over a large portion of the frond, containing minute 

 spores. Tetraspores forming dense band-like sori, 

 beneath the outer substance of the frond. Common 

 on rocks and stones in the sea. Perennial. 

 Autumn and winter. The fronds of this species 

 are stated to be eaten by the poor, either raw or 

 after being pinched with hot irons, when the taste 

 is said to resemble roasted oysters. 



CATENELLA. 



Name meaning a little chain. 

 Frond dull purple, membranaceous, filiform, con- 

 stricted at intervals ; composed internally of a lax 

 network of interlacing filaments. Fructification : 

 1. Masses of spores (favelUdia) contained in ex- 

 ternal capsular bodies. 2. Tetraspores immersed. 



CATENELLA OPUNTIA.— OPUNTIA-LIKE 

 CATENELLA. 



Fronds from half an inch to an inch high ; con- 



