670 University of California Publications in Botany [Vol. 8 



furcatus forms. It is placed in the fu renins group on account of the 

 color, dark olive green to dark olive brown, and the presence of 

 caecostomata in abundance. 



Many of the terminal segments are very broadly ovate, almost 

 stipitate. on account of the narrowing of the bases, producing broad 

 rounded angles between the segments. The growing points differ from 

 those of all other forms observed on our coast, the apices of the seg- 

 ments being rounded and smooth, but with slight inconspicuous slits 

 to indicate the position of the growing point. 



The receptacles, particularly when young, have the pronounced 

 and distinguishing character of spreading very widely from each other 

 at their bases, in some instances standing at right angles, or even 

 more, to each other. Many segments have the character of reducing 

 their width at each forking, the terminal segments forming the stipe- 

 like portion bearing the much wider receptacles. 



8. Fucus furcatus f. latifrons Gardner 

 Plate 101 



Fronds decidedly foliaceous, contorted, comparatively thin, 25-35 

 cm. long, dark olive brown below, light brown above, black on drying, 

 dichotomous, angles mostly acute; segments cuneate, terminal seg- 

 ments mostly rounded, 2-3.5 cm. wide, midrib prominent below, 

 decidedly reduced above, caecostomata 40-80 per sq. cm. ; receptacles 

 not definitely delimited, complanate, bi- tri-furcate, mostly acute ; con- 

 ceptacles large, frequently extending down the midrib, covering a 

 cuneate area of the segment. 



Growing on rocks in the middle and lower littoral belts. Channel 

 Kocks, near Fort Ward, west of Seattle, Washington. 



Gardner, Genus Fucus, 1922, p. 25, pi. 14. Fucus evanescens f. 

 pergrandis, Collins, Holden and Setchell, Phyc. Bor.-Amer. (Exsicc), 

 no. CXI. 



In width of fronds, this form of F. furcatus overlaps or merges 

 into forms of F. evanescens, e.g., forma magnificus. It is here placed 

 under furcatus on account of the dark olive green color, more or less 

 cartilaginous consistency, and particularly on account of the abun- 

 dance of caecostomata. 



It is closely related to F. furcatus f. rigidus, but the fronds are 

 more foliaceous, the receptacles are wider and shorter and the 

 caecostomata are less abundant. 



