vol.i] Setchell— Gardner. — Algce of Northwestern America. 235 



Family HYDRURACE.E. 



Hydrurus fcetidus (Vill.) Kirchner. 



On rocks and stones in cold rapid streams. Near Iliuliuk, 

 Unalaska, Alaska, 11 .A.S. and A.A.L., No. 5042! ; Kukak Bay, 

 Alaska, Saunders (1901, p. 400); Juneau, Alaska, TV .A.*S'. and 

 A. A. L.. No. 5189!; Vancouver Island, B. C, Harvey, (1862, 

 p. 177). 



This species occurs in several of its forms in each Alaskan 

 locality. 



Family ECTOCARPACEiE. 



Pylaiella litoralis (L.) Kjellman. 



Attacked to various algae or woodwork. St. Lawrence Island 

 and Port Clarence, Alaska, Kjellman (1889, p. 51) ; Norton Sound, 

 Alaska, B. G. McGregor, No. 5678! ; "Fuca Strait" and Esqui- 

 mau, B. C. Harvey (1862, p. 167). 



This very variable species has been divided into a number of 

 varieties and forms by Kuckuek, Kjellman, and other writers. 

 The specimens and references given above are not referable easily 

 under their proper forms and are mentioned here. Below are 

 given such as are more or less readily referred under published 

 varietal and foi-m names. It seems that the following two species 

 are probably to be placed under P. litoralis, also: P. atroviolacea 

 Ruprecht (1851, p. 385) from Sitka and perhaps also from 

 Unalaska, collected by Mertens, and Ectoearpus Aleuticus Kuetz- 

 ing (1860. p. 1, pi. 2. 1) also collected at Unalaska by Mertens. 



Pylaiella litoralis var. opposita f. typica Kjellman. 



On Fucus, St. Michael, Alaska, W.A.S., Nos. 5238y!, 5247x! 

 Pylaiella litoralis var. opposita f. rupincola Kjellman. 



On piles or floating logs. Iliuliuk, Unalaska, Alaska, W.A.S. 

 iiml A.A.L., No. 4025!; LaConner, Skagit County, Wash., 

 X.L.G., No. 339! 



Pylaiella litoralis var. opposita f. acuta Saunders. 



On Fucus, Kukak Bay, but generally abundant from 

 Wrangell, Alaska, to the Aleutian Islands, Saunders (1901, p. 

 418). 



