14 



THE METABOLISM OF ALGAE 



Chr^'sophyceae . Chr^-somonadales Synura, Ochromonas 

 (mainly flagel- Chrysosphaerales — 



lates, fresh- Chr^'sotrichales — 



water and 



marine) 



PYRROPHYTA 



Cr^'ptophyceae , 

 (mainly flagel- 

 lates; freshwater Cr>'ptococcales 

 and marine) 



Dinophyceae 

 (mainly flagel- 

 lates; most 

 abundant in the 

 sea) 



Cr\'ptomonadales Chilomonas*, Crypto- 



(A) Desmokontae 



(B) Dinokontae: 

 Dinoflagellata 



Dinococcales 

 Dinotrichales 



monas 



Prorocentrum 



Gymnodinium, 

 Peridinium 



Euglenineae . 

 (flagellates; 

 most abundant 

 in freshwater) 



EUGLENOPHYTA 



Astasia * Euglena 



Phaeophyceae 

 (brown sea- 

 weeds; filament- 

 ous and more 

 elaborate forms; 

 all but a few- 

 marine) 



Rhodophyceae 

 (red seaweeds; 

 filamentous and 

 more elaborate 

 forms; all but a 

 few marine) 



PHAEOPHYTA 



Ectocarpales 



Tilopteridales 



Cutleriales 



Sporochnales 



Desmarestiales 



Laminariales 



Sphacelariales 



Dictyotales 



Fucales 



RHODOPHYTA 



(A) Bangioideae: 

 Bangiales 



(B) Florideae: 

 Nemalionales 

 Gelidiales 



Coilodesme, Ectocarpus, 

 Myelophycus 



Alaria, Chorda, Lamin- 

 aria, Macrocystis, Sac- 

 corhiza 



Ascophyllum, Fucus, 

 Pelvetia 



Porphyra, Porphyridium 



Gelidiwn 



Cr>'ptonemiales Corallina, Harveyella* 



