FRESH-WATER A L G .^ OP THE UNITED STATES. 71 



Eah. — In rupibus irroratis inter muscis minutis. Mount Tahawus (vulgo Mount Marcy),' alt. 

 5000 feet. 



Forming a blackish, widely expanded, tomentose turfy covering to rocks ; filament with scat- 

 tered branches ; branches mostly single, often elongate and clavate ; cells uniseriate, about 

 equal, or shorter than long, sometimes subglobose, often subquadrate ; in advanced age often 

 strongly compressed iind transversely oblong from mutual pressure, yellowish, or sometimes, 

 when young, greenish ; the apical cells coalescent into an irregularly cylindrical mass ; hete- 

 rocysts wanting ; sheaths yellowish-brown ; at maturity more or less subopaque, and distinctly 

 lamellate; in youth more or less transparent, and sometimes colorless. 



Remarhs. — Near the top of Mount Tahawus, in the Adirondack Mountains, 

 tliere is, at an altitude of aboiit five thousand feet, a steep slope of bare rock, 

 the bed of an old landslide, over portions of which water is continually drip- 

 ping. In such places the plant luidcr consideration flourishes, forming with 

 some very minute mosses a blackish, turfy coating to tlie rock of many feet, 

 or even yards, in extent. The specimens agree well with the descriptions of tlie 

 European plant, which also grows at about the same altitude as the American. 

 They have, however, one pecidiarity not noted in description of the European 

 form, namely, that oftentimes the slieath of a branch Avidens out until it is actually 

 much larger than the main filament. The color of the cells in the European form 

 is said to be seruginous ; but I conceive this depends somewhat upon the age of 

 the specimens and is scarcely of primary value. Tlie only other difference wortli 

 noticing is that my measurements exceed somewhat those given of the European 

 plant. I do not think, however, there is any good ground for separating the forms 

 as distinct species. 



The finding of an Alpine plant growing on a mountain half way across the world 

 from its first discovered home, at practically the same altittidc, is a matter worth 

 noting as a fact in Botanical Geography. 



S. neg^Iectiis, Wood. 



S. immersus; trichomatibus subsolitariis, longis usque ad lineas quatuor, cylindricis, raraossis- 

 simis ; ramulis singulis; cytioplasmate interdum ajrugineo, plerumque aureo-brunneo; cellulis 

 uniseriatis rarissime biseriatis, subglobosis, interdum sejunctis sed plerumque arete connectis 

 et moniliformibus, modo conflucntibus, hand distincte pachydermaticis ; cellulis terminalibus 

 elongato-cylindricis, sa^pe nonnihil oscilatorium modo articulatis ; cellulis interstitialibus nullis ; 

 Taginis interdum brunneis, plerumque coloris cxpertibus. 



Dmm.— Trichom. cum vag. ■^\^" = .0017" ; sine vag. y^Vu" = OOl"- 



Syn. — S. ncglectus, Wood, Prodromus, Proc. Amer. I'hilos. Soc, 1SG9, p. 133. 



Hab. — In stagnis, New Jersey. 



S. immersed, subsolitary, attaining a length of 4 lines, cylindrical, very much branched ; branches 

 single ; cytioplasm seruginous, mostly yellowish-brown ; cells uniseriate, very rarely biseriate, 

 subglobose, sometimes separate but more frequently closely united and moniliform ; terniinal 

 cell an elongated cylinder, often articulate somewhat like an oscillatoria ; interstitial cells 

 ■wanting ; sheaths transparent, sometimes brown, mostly colorless. 



' " Tahawus" cloud splitter. The Indian names of the American mountains ought to be retained, 

 in spite of the fact that some vulgar land surveyor has defiled the Adirondacks with the names of 

 politicians, through whose influence he hoped for patronage. 



