UNIVERSITY OF CALIFORNIA PUBLICATIONS 



IN 



BOTANY 



Vol. 6, No. 14, pp. 377-416, plates 31-35 June 30, 1917 



NEW PACIFIC COAST MAEINE ALGAE I 



BY 

 NATHANIEL LYON GARDNER 



LIMfAKV 

 ••TAMICAi, 



Arthrospira maxima Setchell et Gardner sp. no v. 



Plate 33, fig. 3 



Natans, aeruginea, in algis aliis intermixta ; trichomatibus 7-9u 

 diam., laxe et aperte spiralibus, 3-8 flexubiis compositis, 40-6()ju. diara., 

 anfractibus lO-SOfx inter se distantibns, non torulosis; celhilis 5-7/i 

 longis, dissepimentis distinetis ; granulis numerosis, crassis, angnlatis, 

 ref ringentibnsque et in dissepimentis frequenter dense aggregatis ; 

 cellula apicalibus rotundatis, membrana leviter incrassatis. 



Triehomes l-d/x diam., forming an open regular spiral of 3-8 turns 

 40-60/i diam., 70-80ju, between the turns, slightly tapering at the ends ; 

 cells 5-7/x long, not constricted, with numerous, coarse, angular, re- 

 fringent granules frequently crowded at the partitions ; end walls of 

 the terminal cells rounded, slightly thickened ; color verdigris. 



Floating in abundance among other species of Cyanophyceae in 

 warm salt water. Kev Route Power-house, Oakland. California. 

 July, 1916. 



The habitat of Arthrospira maxima is rather unusual. The salt 

 water is pumped from San Francisco Bay into a series of ponds of 

 considerable size. It is then pumped through the electric power-house 

 for condensing steam ; it there becomes heated to about 60° C, and 

 is then allowed to run out where it is cooled again to the temperature 

 of the air before being pumped back into the power-house. It thus 

 appears that the plant is subjected to these rather unusual extremes 

 of heat several times a day and j'et thrives abundantly. 



The genus Spiruli'na was established hy Turpin in 1827 (Turphi, 

 1827, p. 309). He did not mention the transverse cell walls. These 

 cell walls are quite obscure in the small forms of the genus, and this 

 fact led later algologists to regard them as unicellular plants. In 

 1852, Stizenberger (1852, p. 32) founded the genus Arthrospira to 





