368 



BOTANY 



PART II 



The cells of the Phaeophyceae have usually but one nucleus. They 

 contain a larger or smaller number of simple or lobed, disc-shaped 



Fio. 201.— Fucus scrratus. To the left the end of an older branch bearing conceptacles. (i^ nat. size.) 



chromatophores, which contain a brown pigment (phaeophyll, p. 

 62), giving to the algae a yellowish-brown or dark-brown colour. 

 Numerous grains of a semi-tiuid substance, to which the name 

 fucosan has been given, appear as the product of assimilation. 



