THE ALG^E 



123 



Affinities of Characeae 



The Characeae show no very evident affinity with any other group 

 of plants. Perhaps, on the whole, they most nearly resemble some 

 of the Siphoneae, but the relationship, if it exists, is very remote. 

 Certain resemblances in the reproductive organs have suggested a 

 possible affinity with the Mosses, but this is, to say the least, 

 exceedingly problematical. 



Fossil Characeae. Abundant remains of Characese are found fossil, 

 but not in the older formations, and all remains so far discovered 

 are closely related to existing forms, and throw no light upon the 

 origin of the group. 



CLASS II. PH^EOPHYCEJE (BROWN ALG^E) 



Except the Diatoms and some of the Peridineae, which may pos- 

 sibly be very remotely 

 related to the true 

 Phaeophyceae, the Brown 

 Algae are essentially 

 marine plants, and, with 

 the Red Algee, make up 

 the bulk of the shore 

 vegetation of the Ocean. 

 Among the Phaeophyceae 

 are found some of the 

 giants of the vegetable 

 kingdom. 



Color. The Brown 

 Algae, as their name 

 indicates, possess, in 

 addition to the chloro- 

 phyll, certain brown or 

 yellow pigments, of 

 which two are demon- 

 strable, phycoxanthine 

 and phycophaeine, the 

 latter being soluble in 

 fresh water. The mix- 

 ture of these pigments 

 has been termed " Phaeo- 

 phyll." 



Plant-body. None of FIG. 94. ^, Tolypella sp. (X20). B, Nitella sp. 

 the true Phaeophycese C, Chara coronata (X40). ?, oogonium; 6, an- 



n , ,1 theridium. 



are unicellular, the sim- 

 plest being cell-rows, as in Ectocarpus, or flat disks (e.g. Phycocelis). 



