694 University of California Publications in Botany [Vol. 8 



15. Fucus evanescens f. limitatus Kjellm. 



Fronds caulescent or subcaulescent, submembranaeeous, dicho- 

 tomous, spreading, with rounded angles, yellowish brown, darker brown 

 on drying; segments short, cuneate-linear, apices rounded, truncate, 

 midrib distinctly reduced upward, cryptostomata few ; receptacles dis- 

 tinctly delimited, subpedicilate, seemingly lateral, entire or bifurcate, 

 ovoid-ellipsoidal, 12-18 mm. long, 8-12 mm. wide. 



Growing in the upper sublittoral belt. Port Clarence to Norton 

 Sound, Alaska. 



Kjellman, Om Beringh. Algflora, 1889, p. 34 ; De-Toni, Syll. Alg., 

 1895, p. 202 ; Setchell and Gardner, Alg. N.W. Amer., 1903, p. 282 ; 

 Gardner, Genus Fucus, 1922, p. 54, pis. 58, 59. 



Kjellman, Port Clarence, Alaska; R. C. McGregor, no. 5683 (Herb. 

 Univ. Calif., no. 99107), Besboro Island, Norton Sound, Alaska. 



The only material of which we are aware that has previously been 

 referred to this form since its establishment by Kjellman is that 

 referred by Setchell and Gardner (loc. cit.) from Norton Sound, and 

 the same material, two small fragments of plants, is again referred 

 here to the same form, though with some doubt. It is evidently a 

 small form, and according to Kjellman, grows in the sublittoral belt, 

 an unusual habitat for small forms, or even other forms outside of the 

 Arctic regions. 



16. Fucus evanescens f. angustus Kjellm. 



Fronds subdichotomously branched, 20-30 cm. high, 4-5 mm. wide, 

 coriaceous or submembranaeeous; segments linear or cuneate-linear, 

 elongated, midrib distinct below, becoming inconspicuous or almost 

 vanishing at the apices, cryptostomata prominent, variable in number ; 

 receptacles small, oblong, ovoid to broadly ellipsoid, obtuse or acute 

 inflated or more or less complanate ; conceptacles hermaphroditic, 

 antheridia at times sparse ; color black on drying. 



Kjellman. Algenveg. Murm. Meer., 1877, p. 27 ; Gardner, Genus 

 Fucus, 1922, p. 56. 



This form of evanescens, first described by Kjellman, has not been 

 clearly identified with any specimens from our region, but is here 

 included because of its close resemblance to certain of our forms, and 

 hence the probability of its occurrence within our waters would seem 

 to warrant its inclusion. 



