[417] THE ALG^ 181 



In the branches of Liehmannia sp. from Sitka (i42(5). 



A very minute plant the erect branches of which might easily be taken 

 for a part of the host plant. The penetrating filaments are 1-2 /z 

 wide, short, sparingly branched ; cross partitions few and inconspicu- 

 ous, at intervals closely applied to the host cells ; no hairs or unilocu< 

 lar sporangia were observed. 



Streblonema pacifica sp. nov. (Plate xlv, fig. la and i3.) 



Plant composed of irregular branching horizontal threads, from 

 which arise mostly unicellular, haustoria-like filaments which pene- 

 trate into the host plant, and erect filaments arising at right angles to 

 the horizontal ones ; cells of the horizontal filaments 4-8 /i wide, twice 

 as long as the diameter ; erect filaments short, unbranched or once di- 

 chotomous, 30-70 p. long, most of them bearing a narrow elliptical plu- 

 rilocular sporangium 5;^ and 13 y^, which contains about five uniseriate 

 zoospores. The plant forms circular dark brown patches 2-4 mm. in 

 diameter on the sporophylls of Alaria. Related to Streblonema minu- 

 tulutn of Heydrich, but larger in all its measurements. 

 Yakutat Bay (438) . 



Streblonema irregularis sp. nov. (Plate xlv, fig. 2.) 



Plant consisting of irregularly branching surface filaments applied 

 closely to the host plant, from which arise numerous simple or spar- 

 ingly branched erect filaments 1-2 mm. high, 9-14 p. wide, cells as 

 long to twice as long as broad ; from the surface filaments, filaments 

 10-14 II wide, with cells a little shorter or longer than broad, penetrate 

 the substratum irregularly ; plurilocular sporangia linear, lanceolate or 

 ovate, terminal or lateral on the erect filament, 14-18 a* wide, 55-70 At 

 long ; no unilocular sporangia observed. 



Forming small brown patches on the bulbs of Nereocystis ;priafus^ 

 Sitka (164). 



This plant is closely related to Streblonema stilophorea in its gen- 

 eral appearance and method of branching, but differs from it in the 

 shape of the sporangia and the chromatophores of the vegetative fila- 

 ments which are small, round and numerous in this species. 



Ectocarpus tomentosus (Huds.) Lyngb. 



Abundant on Fucus evanescens^ Sitka harbor (166), and Victoria, 

 British Columbia (49). 



The rope-like tufts of the Alaskan specimens are fully as long as 

 those from the Atlantic ocean, while the specimens from the Califor- 

 nia coast are rarely over three mm. in length. 



