1925] SetcheU-Gardner: Melanophyceae 547 



Since the foregoing was written, we have been allowed, through 

 the kindness of Professor C. H. Ostenfeld, to examine one of Lyngbye's 

 specimens of Linckia Zosterae. It is clearly very closely related to 

 Eudesme virescens as we understand it. We, therefore, feel justified in 

 assuming that Mgwa is synonymous with Eudesme. 



JEgira, virescens (Carm.) S. and G. 



Plate 42, figs. 59, 60 



Fronds very flaccid and gelatinous, 8-20 cm. (up to 45 cm.) high; 

 branches arising from the main frond at wide angles, numerous, 

 variable in length, usually enlarging above, blunt ; the ultimate ramuli 

 short, arising almost at right angles; medullary filaments few to many 

 very loosely bound together, composed of cells very variable in size 

 even in the same filament, up to 55/* diam., 1.5-2.5 times as long as the 

 diameter, constricted at the cross-walls, with numerous, small, disk- 

 shaped chromatophores, giving rise to longer or shorter lateral, color- 

 less, branched filaments bearing in turn the loose fascicles of free, 

 branched, assimilating filaments, zoosporangia, and long colorless hairs, 

 the latter terminating the colorless branches; cortical assimilating 

 filaments slender, branched, tapering slightly at the apices, terminal 

 ramuli 10-15 cells long, fascicled, arcuate, cells cylindrical below, 

 becoming slightly moniliform above, 15-20/* diam. ; hairs numerous, 

 long, terminating the lateral branchlets from the medullary filaments ; 

 zoosporangia broadly ellipsoidal, short cylindrical, obovate to rhombic- 

 ovate, arising near the outer ends of the colorless lateral filaments, 

 70-90/* (up to 120/*) long, 25-65/* broad; gametangia short, lateral 

 and seriate, secund on the cortical filaments. 



Growing on rocks and on eel grass in the littoral and sublittoral 

 belts. Shumagin Islands to Sitka, Alaska. 



Setchell and Gardner, Phyc. Cont., VII, 1924, p. 11. Eudesme 

 virescens Saunders, Alg. Harriman Exp., 1901, p. 423 (?); Setchell 

 and Gardner, Alg. N.W. Amer., 1903, p. 249. Liebmannia sp. 

 Saunders, loc. cit., p. 424, pi. 49 ( ?). Mesogloia virescens Carmichael, 

 in Hooker, Engl. PL, vol. 2, 1833, p. 387. 



While we suspect that the plant referred by Saunders to Eudesme 

 virescens and so referred to by us in our Algae of Northwestern 

 America ( loc. cit.), may be the same species as that collected by one of 

 us at Sitka, we have not been able to examine a specimen to make 

 certain. Our plants show no gametangia but have zoosporangia and 



