BOT.-VOL. II.] HUS—PORPHYRA. 223 



Localities. — Yakutat Bay, Alaska (de A. Saunders, No. 

 214!); Baranoff Island, Alaska (de A. Saunders, No. 136!, 

 No. 137!, No. 148!); Shumagin Island, Alaska (de A. 

 Saunders, No. 384!). 



13. Porphyra abyssicola Kjellm. 



Algae of the Arctic Sea, 1883, p. 191. 



Porphyra abyssicola Kjellman, Algce of the Arctic Sea, 1883, p. 191; PI. 17, 

 fig. 4; PI. 18, figs. lo-ii. FosLiE, Cont. to Knowledge of the Marine 

 Algce of Norway, I, 1890, p. 60. Hus, Zoe, Vol. V, 1900, p. 68. de 

 ToNi, Sylloge Algarum, Vol. IV, 1897, p. 14. 



Fronds membranous, 2-10 cm. long, 1-4 cm. broad, lanceolate-obovate, 

 with undulate margins; color livid cerise; base cuneate, sessile with small 

 disc; distromatic, often monostromatic, 25//- thick; cells of the middle of the 

 frond square or nearly twice as long as broad, with rounded angles; fronds 

 monoecious, often dioecious; when monoecious antheridia and sporocarps 

 intermixed in a marginal zone, 2-4 carpospores to each sporocarp, 8 anther- 

 ozoids to each antheridium. 



This species is known to the author by some twelve spec- 

 imens found among a number of specimens of P. naiadiim 

 growing on Zostera. They agree in every respect with the 

 description of P. abyssicola of Kjellman. Only a few of 

 the specimens were fertile. On examination it was found 

 that some were monoecious and others dioecious. 



The specimens examined grew on Zostera, and were 

 easily distinguished by their more elongated frond and by 

 the absence of the characteristic cushion-shaped base of 

 P. naiadum. The plants of P. abyssicola were also deeply 

 though sparsely plicate. • 



In this species the difficulty of assigning it to the mono- 

 stromatic or distromatic group makes itself more felt than 

 in any other case. The specimens which were available 

 for examination were for the greater part distromatic, and 

 I hesitated considerably before assigning them to P. abyssi- 

 cola. But it must be remembered that plants of this group 

 vary considerably in this regard, and since all other char- 

 acters were those of Kjellman 's P. abyssicola, they were 

 finally assigned to this species. 



