210 PEACTICAL BOTANY 



There are no known unicellular red algee. Usually the plants 

 are quite complex and present expanded leaf-like structures 



Fio. 173. A red alga [Gicjartina spinosa) 

 Attached by means of its holdfast to a small stone 



(Fig. 173) or are extensively branched (^Fig. 174). They have 

 basal holdfasts, which in general jx'semble those usually found 

 in the brown algte. Red algaj are, as a rule, smaller and 



