184 SAUNDERS [4 20 ] 



Homeostroma lobatum sp. nov. (Plate XLVI, figs. 60, 6<5, 6c.) 



Plant broadly linear, lanceolate or ovate, 10 or more cm. long, 15 



cm. wide, narrowed below to a short stipe, dark olive-brown; the 



edges deeply and irregularly lobed, the lobes irregularly cut and divided ; 



unilocular sporangia scattered over the whole surface of the plant. 

 Attached to Zostera marina. Sitka (114) ; Prince William Sound 



(296). 



Cross sections of the young plants were two cells thick, those of the 

 older plants 4 cells thick, the central cells slightly larger than the outer 

 but not at all elongated. No plurilocular sporangia were observed. 



Homeostroma latifolium (Grev.) J. Ag. 



Occasional in quiet sandy coves. Annette Island (39) ; Sitka (143) ; 

 Popof Island (367). 



Punctaria plantaginea Grev. 



On exposed rocks near entrance to Yakutat Bay (229). 



The plant is 410 mm. wide, and 5-10 cm. long. Both unilocular 

 and plurilocular sporangia are abundant. Some of the specimens 

 approach Foslie's variety linearis^ 



Myelophycus intestinalis sp. nov. (Plate XLVII.) 



Plant dark reddish brown, loosely caespitose, cylindrical, hollow 

 with age, much twisted and intestiniform, narrowed below to a dis- 

 tinct solid stipe, 512 mm. long; the inner layer of tissue composed 

 of long colorless cells, the intermediate layer composed of 24 irregu- 

 larly arranged rows of thick-walled cuboidal cells giving rise to broad 

 coarse paraphyses composed of 4-8 thick- walled cells ; sporangia very 

 abundant, elliptical or obovate, scattered irregularly throughout the 

 frond, 45 6o/j. long, 20-30 /j. wide, arising like the paraphyses from 

 the intermediate layer of tissue. 



Attached to rocks in the sublittoral zone from Puget Sound to the 

 Shumagin Islands. More abundant in quiet coves. Glacier Bay 

 (113); Sitka (192); Yakutat (252); Popof Island (359); Puget 

 Sound (Gardner 215). 



This plant was at first referred tentatively by the writer to Foslie's 

 Chordaria attenuata. Foslie states 2 however that this plant is a form 

 of Scytosiphon ; Mr. F. S. Collins has kindly examined specimens of 

 Foslie's plant and agrees that it is a Scytosiphon and quite distinct 

 from the Pacific plant. M. intestinalis is less firm in texture and is 

 lighter colored than Kjellman's M. c<zspitosa\ in cross section the 



Leslie, Om Nogle Arctiske Havalger. 

 *Nya Havalger, Vol. 13 : 97. 



