NOTES ON THE ECOLOGY AND ECONOMIC IMPOR- 

 TANCE OF NEREOCYSTIS LUETKEANA 



A CONTRIBUTION FROM THE PUGET SOUND MARINE STATION 



GEORGE B. RIGG 



University of Washington, Seattle, Washington 



Nereocystis luetkeana is the most abundant kelp of the Puget 

 Sound region. The huge size of the individual plants, the fact 

 that its bladder-like float is always at the surface of the water 

 where it can be seen, and the fact that it forms dense beds cover- 

 ing such large areas bring it to the attention of every observer who 

 crosses the waters of Puget Sound. Attaching itself to rocks by 

 means of its powerful much-branched holdfast, it thrives in strong 

 tideways. The slender rope-like stipe is strong and flexible. It 

 enlarges upward into a hollow pneumatocyst which gradually 

 increases in size until it terminates in a hollow bulb at the top. 

 The pneumatocyst of a mature specimen is commonly constricted 

 slightly just below the bulb, upon which are borne numerous slen- 

 der ribbon-like laminae. These, as MacMillan 1 has observed, 

 appear on hasty examination to be two groups of fronds, but on 

 more careful examination it is seen that there are really only two 

 fronds and that these are divided so nearly to the base as to give 

 the appearance of numerous ones. Nereocystis luetkeana is known 

 as the " bladder kelp." In the Puget Sound region the fishermen 

 and navigators more commonly speak of it simply as "kelp." 

 It is abundant from the Shumagin Islands in Alaska to Santa 

 Barbara channel on the coast of California. 2 



The work on which this article is based was done at the Puget 

 Sound Marine Station during the summers of 1908, 1910 and 1911. 



1 MacMillan, C. Observations on Nereocystis, Bull. Torr. Bot. Club, 26: 

 273. 1899. 



2 Setchell, W. A. and Gardner, N. L. The algae of northwest America. 

 Univ. Cal. Pub. Botany, vol. 1. 1903. 



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