276 University of California Publications. I botany 



This species takes the place of Macrocystis along the northern 

 shores of our territory, in forming beds of kelp off rocky shores in 

 waters of several fathoms depth. Its fronds are anchored and 

 the stipe, bunch of sporophylls and much of the blade is sub- 

 merged, but the long blade, reaching a length of 10-25 meters, 

 rises to the surface and, buoyed up by the inflated midrib, 

 generally floats for some distance on the top of the water. The 

 plants are gregarious, and often form belts a longer or shorter 

 distance from the shore as the Macrocystis does farther south. 

 Like the Macrocystis and the Nereocystis, it is commonly met with 

 floating and often in considerable quantity. While passing 

 through Unimak Pass, between Bering Sea and the Pacific Ocean, 

 the surface of the broad expanse of waters is commonly seen to 

 be thickly covered with the floating blades of this species, and it 

 was observed in fair abundance all along the coast of Alaska 

 from the latitude of the Pribilof Islands in the Bering Sea 

 to Wrangell Narrows in southeastern Alaska. It was carefully 

 watched for to the south of the last mentioned locality, but no 

 trace of it was seen. The species varies much, particularly in 

 the width of the blade and shape of the sporophylls. As these 

 plants are of different habitats, it has seemed best to enumerate 

 the specimens actually examined and observed growing, under 

 the forms described below. The stipe of this species seems to be 

 free from mucilage ducts, but the blade in both forms possesses 

 abundant structures of this kind, just under the outer layer of 

 cells as Guignard has indicated (1892, p. 43). 



Alaria fistulosa f. stenophylla Setchell. 



Blade narrow, usually not over 30 cm., with narrow midrib. 

 Sporophylls usually short and more or less decidedly obovate. 



Forming the greater portion of the growth in belts just off 

 shore and isolated bunches in quiet waters of 5 to 10 fathoms. 

 Kyska Island, Alaska, Toivnsend, No. 5769!; plentiful in the 

 Bay of Dnalaska, both on the shores of the Island of Unalaska 

 and the shores of the Island of Amaknak, Alaska, W.A.S., 

 A.A.L., and L. E. Hunt, Nos. 32731,4096!, and in Collins, 

 Holden, and Setchell, P. B.-A., No. XLIII!: Harvester Island. 

 Uyak Bay, Kadiak Island, Alaska, W.A.S. and A.A.L., No. 



