78 CLASS I.— ORDER II. 



seen at the bottom of the cell, dried, in the form of a 

 little opaque globule. 



The substance of the Dynamenas is membranous 

 or horny. 



In the bosom of the sea they are adorned with 

 brilliant colours, which fade or disappear by exposure 

 to air and light. 



All the species, with the exception of the Opercu- 

 lata, scarcely reach a few centimetres in height, al- 

 though their growth appears rapid : they are usually 

 parasites on the Thalassiophytes, or the other marine 

 productions of the different seas that cover the face of 

 the globe. 



OPERCULATED. 



1. Dynamena operculata. Cells oval, and closed 

 by a lid terminating in a sharp point. 



Seas of Europe and America. 



WILD PINE. 



2. Dynamena pinaster. Stem simple, pinnated ; 

 pinnies alternate ; cells curved. 



EVANS'S. 



3. Dynamena EvansiL Branches opposite ; cells 

 very short; ovaria lobed and opposite. 



Coast of England, near Yarmouth. 



SERTULARIOUS. 



4. Dys AME^ A sertulario'ides. Stem thick, short, and 

 branching ; branches alternate ; cells often nearly al- 



