20'J 



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 chromatopnores. 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 [j. or even more ; on the other 



14 



