PH^EOPHYCE^E 



83 



FIG. 17. a, transverse section of leaf of Postehia, showing furrows ; 6, 

 transverse section of furrow with sporangia ; c, sporangia and paraphyses ; 

 d, transverse section of frond of Macrocystis; e, transverse section of a 

 furrow with sporangia ; /, sporangia and parphyses. Variously magnified. 

 (After A. L. Smith and F. G. Whitting, in Phyc. Mem.) 



G 2 



