THE KANSAS UNIVERSITY 

 SCIENCE BULLETIN. 



VOL. IX, No. 1.] DECEMBER, 1914. [^°£KS!i. 



A Preliminary Study of the Causes that 

 Produce "Bald-headed" Kelp. 



BY RUPERT PETERS. 



IN sailing or rowing about the San Juan Archipelago in 

 Puget Sound, one is almost constantly within sight of 

 the kelp beds. The typical plants have a large float, or pneu- 

 matocyst, on the surface from which many broad, flat fronds 

 stream outward, in many cases for twelve or fifteen feet. Yet 

 among these plants are many that have lost part or all of their 

 fronds, and the rounded shiny pneumatocyst bulb suggests the 

 term ''bald-headed." Since the kelp is recognized as a source 

 of potash for agricultural fertilizers, the loss of a considerable 

 per cent of the fronds reduces the weight that might be har- 

 vested very seriously, over two-thirds in many cases. 



This subject was suggested to the writer by Dr. R. B. Wylie 

 of the University of Iowa, a member of the U. S. kelp in- 

 vestigation staff during the summer of 1913, following a con- 

 siderable discussion of the kelp, Nereocystis luetkeana, and 

 as full a statement as he was at liberty to give concerning the 

 work being done by that staff. These obesrvations were made 

 in connection with work at the Puget Sound Marine Biolog- 

 ical Station, June-August, 1913. It is to be regretted that 

 observations did not begin early in the term, since many plants 

 were without fronds when observations began, while others 

 were still in vigorous growth. 



Facilities for getting from place to place were limited and 

 the observations were confined almost entirely to the neigh- 



(3) 



