640 University of California Publications in Botany |Vol. 8 



4. Alaria marginata Post, and Rupr. 

 Plate 66 



Stipe moderately short, 2-5 cm. long, 3-5 mm. diam., nearly terete ; 

 rhachis flattened, up to two times as thick as the stipe, merging grad- 

 ually into the midrib ; blade 2.5-3 m. long, 15-20 cm. wide, nearly 

 linear, somewhat tapering above with abruptly cuneate base, produc- 

 ing numerous cryptostomata with abundant exserted hairs ; midrib 

 variable in width, from 5 mm. in some individuals up to 22 mm. in 

 others, merging abruptly into the blade ; sporophylls ovate, lanceolate 

 or elliptical, rounded above, 10-20 cm. long, 2-3 cm. wide, coriaceous, 

 rigid, usually plane, 24-40 in number, sori in some individuals 

 covering both sides completely except a narrow margin, in others only 

 the basal half or third. 



Growing on exposed rocks or in sheltered coves in the middle and 

 lower littoral belts. Fairly abundant along the central California 

 coast, possibly also in Puget Sound. 



Postels and Ruprecht, Illus. Alg., 1840, p. 11 ; Setchell, Kelps of 

 the U. S. and Alaska, 1912a, p. 162, Notes on Kelps, 1896, p. 41. Critical 

 Notes on Laminariaceae, 1908a, p. 9 ; Yendo, Monogr., 1919, p. 93, pi. 6, 

 figs. 1-4. A. curtipes Saunders, A New Species of Alaria, Minn. Bot. 

 Studies, 1901a, p. 561, pi. 33; Tilden, American Algae (Exsicc), no. 

 521 (at least in part). Alaria cordata Tilden, Amer. Alg. (Exsicc), 

 no. 241 (fide Yendo). A. lanceolata ( ?) Collins, Holden and Setchell, 

 Phyc. Bor.-Amer. (Exsicc), 1901, no. XLTV (not of Kjellman). 



The first notice of this species of Alaria appeared in 1840, in the 

 above mentioned publication of Postels and Ruprecht. Later Ruprecht 

 (Tange, 1851, p. 355) referred to A. marginata as being rare, and 

 known to him only from Fort Ross on the California coast. One 

 of us (Setchell) has examined a good specimen of Alaria in the Herb. 

 Acad. Sci. Petrograd, labeled A. marginata "Unalaska — Wosnes- 

 senski," which is like our California species which we have placed 

 under A. marginata Post, and Rupr. No later discovery of this species 

 has been made in the original locality, Unalaska, although careful 

 search has been made for it by one of us (Setchell), and it seems quite 

 probable that the Wosnessenski plant may have come from Fort Ross, 

 California. Hence we take this plant as the type of A. marginata 

 Post, and Rupr. and Fort Ross as the type locality, and place all of 

 the California plants, except A. nana Schrader, under that name at 



