Vol. i| SeicheU-Gardner. — Alg(e of Nopiliwestern America. 283 



FUCUS evanescens f. robustus Setehell and Gardner f. iiov. 



Caulescent with the stipe stout and erect, 15-18 cm. high, 

 broad above, 2-2.5 cm. wide, midrib narrow and distinct to just 

 below the apices, with broad oblong ovate or obcordate, short, 

 flat, margined receptacles. 



St. Paul Island, Alaska, Greeley and Snodgrass, No. 5805! 

 (cf. Setehell, 1899, p. 593, under F . platy carpus f) ; Sitka, Alaska, 

 Ida M. Rodger s, No. 5724! 



The type is No. 5724, from Sitka. The form resembles the 

 last, but is more robustly caulescent, the foliaceons portion is 

 thicker, while the receptacles resemble those of typical F. platy- 

 carpus Tliuret, from which it is to be distinguished l)y its lack of 

 strongly pronounced pinnate habit. From f . dendroides, which 

 it resembles in its arborescent habit, it is to be distinguished by 

 the l)roader foliaceous frond and the broader receptacles. 



Fucus evanescens f. cornutus Kjellman. 



On rocks in exposed places, low^er portion of the litoral zone. 

 Popof Island, Kukak Bay, Prince William Sound, Yakutat Bay, 

 and Juneau, Alaska, Saunders (1901, p. 432); Yakutat Bay, 

 A\Riiksi,Rev.Alhin Jo]inson,^o. 5719! ; Esquimalt, B. C, N.L.G., 

 No. 625!, in Collins, Holden and Setehell, P. B.-A., No. 927! 



To be distinguished by its forked, often swollen receptacles 

 whose branches are pointed and horn-shaped. The form varies 

 somewhat. No. 5719 is a very large plant, 30 cm. high and 

 rather broad winged in the upper part for this form. 



Fucus evanescens f. longifructus Setehell and Gardner f. 



no v. 



Somewhat caulescent ])elow, foliaceous above, u]) to 45 cm. 

 high and 1-2 cm. wide, midrib not pronounced. Receptacles of 

 various shapes from short, broad, blunt, and broadly obcordate to 

 elongated and once or twice forked, with the divisions long, 

 curved and pointed. These elongated receptacles give the char- 

 acters of the form and reach a length of 15-18 cm. 



On stones, upper and middle litoral zones in waters much 

 mixed with glacial waters. Orca, Alaska, ]r..4.AS'. and A.A.L., 

 No. 5151!, in Collins, Holden and Setehell, P. B.-A., No. 928! ; 

 Juneau, Alaska, W.A.S. and A. A. L., No. 5180! 



