Marine Algae 



Samples of the commoner seaweeds found in the Aleutian Is- 

 lands were identified by T. C. Frye. The genus Alaria (the most 

 abundant) is found in shoal water along the entire archipelago. 



Its long, brown, leathery fronds are a nuisance in small-boat 

 navigation. The thallus is 4 to 8 inches wide with a bladderlike 

 midrib that is Y-z to 1 inch wide. This midrib remains floating 

 after the sides of the thallus have decomposed and washed away. 

 Masses of Alarm are seen floating detached at sea and piled on 

 the beaches after the first of August. 



Laminaria has a similar structure, but the fronds are wider 

 (as much as 2 feet) and the plant has the general appearance of 

 a slick leather apron. 



Nereocystis, the common bull-whip kelp of the Pacific Coast, 

 has a long, hollow, floating stem increasing in diameter to a 

 bulb at the free end. Very common along the mainland, this plant 

 is observed only rarely west of the Alaska Peninsula. At King 

 Cove, east end of the Peninsula, Nereocystis is definitely the domi- 

 nant kelp as compared with Alaria to the westward. Nereocys- 

 tis, in all cases a single plant drifting at sea or washed up dead 

 en the beach, was seen on the following Islands : Unalaska, East 

 Semichi, Atka, Ogliuga, and Amchitka. 



Fucus is common along the beach; locally it is called "popweed" 

 from the sound made by the bursting of the bladders when they 

 are trod upon (fig. 1). 



The bright-green sheets of sea lettuce, Viva, are on every beach. 



Spongomorpha has the texture and appearance of coarse green 

 moss and grows attached to rocks. On spray-covered rocks, the 

 cylindrical floats of Halosaccion occur in clumps suggestive of the 

 local name "dead man's fingers". 



Cystophyllum is a brown seaweed that occasionally washes up 

 on the beach. It has a mass of fine branches covered with small 

 brown bladders, each of which is the size and shape of a grain of 

 wheat. 



Thallasiophyllum is easily distinguished by its wide brown 

 fronds covered with holes like a colander. 



A number of lime-secreting marine algae, locally called corals, 



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