tained a very heterogeneous assemblage of plants, imcluding 
almost every Alga which is outwardly gelatinous, and whose 
inward structure exhibits a filamentous arrangement. Thus 
such plants as Gloiosiphonia were included in it, as well as the 
Chetophore, and many others equally unlike each other. The 
group to which the name is now restricted, is distinguished by 
having a gelatinous frond of a definite form, filled with radiating 
threads, each of which terminates at its lower extremity in a 
elobular cellule. The plants thus associated have a strong affi- 
nity together, but are not exclusively marine, several of them 
inhabiting fresh water, and others growing on moist rocks. 
Some of the latter have the property of secreting lime in their 
tissues, if not in such a regular manner as the Corallines, in a 
manner approaching to it. None of the marme species exhibit 
this property. 
ig. 1. Patches of RivuLarta Nitipa:—the natural size. 2. Portion of the 
gelatinous frond. 3. Filaments :—magnified. 
ea 
