KET TO THE GENERA. 69 



(r.) Branches clothed : 



1. With rows or circles of closely set, very 

 short spines, which overlap each other, 

 thus covering every part of the frond. 



Cladostephus. 



2. With short, fine, light olive green, delicate 

 fibrils, which fall away and leave bare 

 spines ; or with long darker green pencils 

 of hair-like filaments. Desmarestia. 



V. Frond capillary. 



I . Unbranched. 



Frond small, parasitical on Fucus, tufted. 



Elachista, 

 2. Branched. 



Frond fine, profusely branched ; from a yel- 

 lowish to a bright green ; parasitical on 

 Fucus, Chofda, Clwrdaria and other 

 Algas. Ectocarpus. 



VI. Frond tuberform. 



Fronds look not unlike green tomatoes. 



Leathesia. 



(^>— ^-(sD 



