Chapter V 

 PHYLUM RHODOPHYTA 



Phylum 1. RHODOPHYTA Wettstein 



Order Floridees Lamouroux in Ann. Mus. Hist. Nat. Paris 20: 115 ( 1813) . 



Florideae C. Agardh Synops. Alg. Scand. xiii (1817). 



Order pLORroEAE C. Agardh Syst. Alg. xxxiii (1824). 



Division (of order Algae) Rhodospermeae Harvey in Mackay Fl. Hibern. 160 

 (1836). 



Class Heterocarpeae Kiitzing Phyc. Gen. 369 (1843). 



Class Florideae J. Agardh Sp. Alg. 1: v (1848). 



Rhodophyceae Ruprecht in Middendorff Sibirische Reise 1, Part 2: 200 (1851). 



Stamm Florideae Haeckel Gen. Morph. 2: xxxiv (1866). 



Phylum RHODOPHYTA Wettstein Handb. syst. Bot. 1: 182 (1901). 



Division Rhodophyceae Engler Syllab. ed 3: 18 fl903). 



Phylum Carpophyceae Bessey in Univ. Nebraska Studies 7: 291 (1907). 



Phylum Rhodophycophyta Papenfuss in Bull. Torrey Bot. Club 73: 218 (1946). 



Definitely nucleate organisms {Porphyridium and Prasiola doubtfully so); with 

 few exceptions living by photosynthetic processes involving red and blue pigments 

 (phycocyanin and phycoerythrin) as well as green and yellow (chlorophylls a and d 

 and carotinoids); not producing true starch, and producing cellulose only in small 

 quantity, the cells walled chiefly with modified carbohydrates which tend to become 

 gelatinous; never producing flagellum-bearing cells, but sometimes producing cells 

 which move in water without the use of definite organelles. 



Tilden (1933) and Smith (1933) are authority for placing the red algae next to 

 the blue-green algae, thus suggesting the inference that they include the most primi- 

 tive of nucleate organisms. The resemblances between blue-green and red algae 

 are in the following points. Both groups possess, along with the chlorophylls and 

 carotinoids usual in photosynthetic organisms, other pigments, both blue and red. To 

 these pigments as found in both groups, the same names, phycocyanin and phycoery- 

 thrin, are applied; they are not, however, the same chemical species (Kylin, 1930). 

 Neither group produces true starch; carbohydrate is stored as substances of the 

 general nature of dextrin or glycogen (occuring in the red algae as solid granules 

 called floridcan starch). Both groups produce cellulose only in scant quantities 

 (Miwa, 1940; Kylin, 1943); the cell walls consist chiefly of materials, of the general 

 nature of carbohydrates, which tend to become gelatinous. They share the negative 

 character of never producing flagella, and the positive one of producing cells which 

 call move actively upon surfaces, without motor organelles, by a mechanism as yet 

 unknown (Roscnvinge, 1927). 



The phylum is divisible into two classes: 



1. Cells of most examples each with one central 

 plastid, without protoplasmic interconnec- 

 tions, in aggregates of indefinite extent or or- 

 ganized as filaments or thalli with intercalary 

 growth; zygotes producing spores directly by 

 division Class 1. Bangialea. 



