vol.i] Setchell-Gardner. — Alga, of North/western America. 327 



Polysiphonia senticulosa Harvey. 



Oreas Island, Wash., Harvey (1862, p. 169). 



This is the type locality for this species. We have seen no 

 plants from our territory which we can refer to it. The species 

 is placed near P. urceolata by J. G. Agardh (1863, p. 974), but 

 is to be distinguished by the terminal branchlets being densely 

 pinnately virgate. If the specimen distributed in Collins, Holden 

 and Setchell's Phycotheca Boreali- Americana (No. 638) is cor- 

 rectly determined, this species differs from the last, not only in 

 the last mentioned particulars, but also in having short but well 

 developed leaves towards the tips both of the main shoot and of 

 the lateral axes. 



Polysiphonia Californica Harvey. 



On rocks and wood, upper sublitoral zone. Escjuimalt, B.C., 

 Harvey (1862. p. 168); Whidbey Island, Wash., N.L.G., Nos. 

 127!. 297!: San Juan Island, Wash., Tilden, No. 316!, under 

 P. atrorubescens; Pleasant Beach, Kitsap County, Wash., N.L.G., 

 No. 347!-. Tracyton, Kitsap County, Wash., Tilden, No. 210!, 

 under P. bipinnata. 



We have made a careful examination of all specimens from 

 our territory with many pericentral cells, accessible to us, of the 

 species of Polysiphonia as limited by Falkenberg (1901). The 

 specimens referred to the present species all agree in having 

 monosiphonous, colorless, simple branchlets (simple leaves?) near 

 the tips of the young axes as Falkenberg has indicated for the 

 type (1901, p. 274). In habit and other details of structure, the 

 plants referred here seem to agree well with the description of 

 Harvey (1852, p. 58) and they also agree well with plants col- 

 lected by us near the type locality and referred here. The rela- 

 tion between this species and P. atrorubescens and P. nigrescens 

 seem likely to be close, but the simple leaves and some differences 

 of habit prevent our referring the specimens to either of these 

 species at present. 



Polysiphonia Californica var. plumigera Harvey. 

 Point Roberts, B. C, Harvey (1862, p. 168) . 



