Feb., 1909.] The Classification of Plants, IV. 449 



17. Florideae. 1835 species. 



Mostly marine red or purple algae, often of considerable size, 

 filamentous or thalloid; reproduction by means of non-ciliated 

 sperms produced in antheridia consisting of definite groups of 

 cells, and eggs produced singly in the base of an oogonium which 

 is prolonged above into a slender trichog}me. Plants with a 

 definite alternation of generations the fertilized egg having a com- 

 plicated development but in the simpler cases giving rise to a ju- 

 venile sporophvte bodv from which one to many carpospores are 

 produced which on germination develop into a second sporophyte 

 stage on which tetraspores are produced from which the game- 

 toph^'te is again propagated. 



18. Chareae. Stoneworts. 160 species. 



Green filamentous erect, mostly freshwater algae, attached at 

 the base by means of rhizoids, with stems distinctly segmented 

 into nodes and internodes, the nodes being marked by whorls of 

 branches; plants usually with an incrustation of lime and the 

 cells of the stem and branches often covered with a cortical 

 layer of smaller cells; without an alternation of generations; 

 oogonia rounded covered by a cortical layer of branches, antheri- 

 dia compound and very complex composed of united branches 

 to form a hollow globular structure containing sperm-bearing 

 filaments; spermatozoids spirally coiled, biciliate; no nonsexual 

 spores present. 



Eumycetae. 



19. Monoblepharideae. 6 species. 



Small coenocytic fungi with a nonseptate or nearly nonsep- 

 tate mycelium, with uniciliated zoospores and with a typical sex- 

 ual reproduction ; saprophytic and aquatic ; eggs stationary in the 

 oogonium which opens to admit the uniciliated spermatozoids. 



20. Zygomycetae. 180 species. 



Saprophytic or parasitic fungi with a nonseptate or nearh^ 

 nonseptate mycelium having a conjugation of equal or nearly 

 equal branches, one of which does not penetrate the other to any 

 extent, the result of conjugation being a simple or coenocytic 

 zygospore; sometimes parthenogenetic ; nonsexual spores usually 

 non-motile. 



21. Oomycetae. 185 species. 



Mostlv parasitic fungi with a nonseptate or nearty nonseptate 

 mycelium, with conjugating branches, the one being much larger 

 than the other which penetrates into its interior, the result being 

 a simple or coenocytic sexual spore ; sometimes parthenogenetic ; 

 nonsexual motile spores also produced which frequently develop 

 in conidia. • 



22. Ascomycetae. 12,250 species, besides 8,250 Lichens and 

 13,500 Deuteromvcetae. 



