1922] Gardner: The Genus Fucus on the Pacific Coast 41 



are smaller, segments narrower and regularly dichotomous instead of 

 subsecund, and the receptacles are shorter and blunter. The only 

 locality from which it has been reported is the one given above ; there 

 it grew in profusion. Doubtless it may be found at other localities on 

 the same bay. 



Fucus evanescens f. dendroides Stroem. 



"P. evanescens subereetus. rigidus, stipite validissimo, trunciformi, 

 basin versus incrassato, longe denudato, in costam supra sensim evanes- 

 centem abeunte ; fronde flabelliformiter dichotoma, segmentis angustis- 

 simis. 2— S mm. latis, mediis costa promiuente alatis summis ecostatis; 

 receptacidis fusiformibus — anguste siliquaeformibus, 1-3 cm. longis, 

 interdum furcatis. minus verrucosis. ' ' 



Stroemfelt, Om Alg.-veg. vid. Islands Kuster, 1886, pp. 35, 36, pi. 3. 

 The type locality is Seley. Iceland. 



Fronds distinctly caulescent, dense, coriaceous. 7-15 cm. high, 

 rigid, terete at the base and for some distance among the main branches, 

 tapering upward, the narrow alae having worn away leaving only the 

 much enlarged midrib, flabellate-dichotonious, in part subsecund, pro- 

 fusely forked, dark olive green to olive brown, black on drying; seg- 

 ments strict, somewhat contorted, narrow, 5-8 mm. wide in depau- 

 perate specimens, cuneate to slightly linear, widest at the truncate 

 apices, growing point slightly depressed, midrib prominent, per- 

 eurrent ; cryptostomata sparse or entirely absent ; receptacles very 

 abundant, single, retuse to bifurcate, subfusiform to ovoid, consider- 

 ably swollen. 1—3 em. long ; eonceptacles numerous, emitting relatively 

 long fascicles of paraphyses. 



Plate 41 



Growing on rocks exposed to fairly heavy surf, in the upper and 

 middle littoral belts. Agattu Island to Sitka, Alaska. 



Townsend. nos. 5755, 5756 (Herb. Univ. Calif., nos. 99105, 99106), 

 Agattu, Alaska; Gardner, no. 2227 (Herb. Univ. Calif., no. 201148), 

 Sitka, Alaska ; Setchell and Lawson, no. 4052 (Herb. Univ. Calif., no. 

 99095. sub Fucus evanescens f. bursiger); Summer Bay, Alaska (cf. 

 Setchell and Gardner, 1903, p. 285). 



Stroemfelt. loc. cit. • De-Toni, Syll, Alg., 1895, p. 203 ; Setchell and 

 Gardner. Alg. N.W. Amer., 1903, p. 284. 



I first observed this plant in June, 1910, growing at Sitka, Alaska. 

 A considerable area near the upper tide limit was completely covered 

 with specimens. The plants were repeatedly branched, fruiting pro- 

 fusely, had a relatively large and strong holdfast and stipe, and varied 

 from 7 cm. to 15 cm. in height. Some of the plants of Setchell and 

 Lawson, referred to above, are only 4 em. high, those of Townsend are 



