F. Borgesen: Rhodophyceæ of the Danish W. Indies. 



209 



filaments emerging higher up from the main stem. Like the main 

 stem these filaments end in rhizoids often growing together to 

 small discs. 



Fig. 194. Mesothamnion caribaeum nov. spec, a — c, quite young and older 



cells showing shape of chromatophores. d, base of a plant. 



{a, b, c, about 200 : 1 ; d, about 40). 



The basal cells in the main stem are comparatively small, 

 but they rapidly increase in size, so that, at a short distance from 

 the base, we find the thickest part of the main stem, the cells 

 here reaching a breadth of 250 ft or even more ; on the other 



Pansk Botanisk Arkiv, Bd. 3. Nr. 1 (1917). 14 



