82 University of California Publications in Botany [Vol. 9 



meadows, Yosemite, Dudley, July 20, 1901; Cloud's Rest, Dudley, 

 June 13, 1894 ; same at 8,700 feet. Smiley 513 ; Mt. Raymond, 8-9,000 

 feet, Bolander ; Bald Mountain, Dinkey Creek, Fresno County, 10,000 

 feet, Hall and Chandler, 372 ; Kaiser Crest, 9,600 feet. Smiley 647 ; 

 near Mineral King, Coville and Funston, 1416 ; summit above Moun- 

 tain Lake, Tulare County, Dudley 934. 



P. monticola in the northern Sierra habitually occurs between 

 7,000 and 8,000 feet, with a lower limit of 6,000 on north slopes and 

 rising in a few places to 9,000. It is often found growing with AMes 

 miagnifica near the upper limit of the fir, and commonly with Pinus 

 Murrayana. In a few places it forms pure stands, as on the ridge 

 between Donner and Webber lakes. In the southern Sierra, it is 

 most abundant on the windward (west) sides of the ranges. At its 

 southern limit in Tulare County it rises to over 10,000 feet (Mountain 

 Lake ) . 



2. Pinus flexilis James, in Rep. Long's Exped., vol. 2, p. 35. 1823. 



Apinus flexilis Eydb., Bull. Torr. Bot. Club, vol. 32, p. 598. 1905. 



Type locality. — "Arid plains subjacent to the Rocky Mountains, 

 and extends up their sides to the region of perpetual frost." 



Range. — Southern Sierra Nevada and mountains of southern Cali- 

 fornia, east to New Mexico and western Texas and north to Alberta ; 

 ranges of the Great Basin. 



Zone. — Canadian, rising to the lower edge of the Hudsonian. 



Specimens ex<amined. — Sedge Meadow near Mt. Whitney, Dudley 

 2468 ; Olancha Mountain, 10,400 feet, Rothrock 350 ; summit of Mt. 

 Pinos, Dudley and Lamb 4593 ; same, Abrams and McGregor 243. 



P. flexilis is usually stated to range southward from Mono Pass 

 on the eastern slope; this station seems to rest on a single collection 

 by Bolander (no. 6045 of the State Survey), and not since repeated. 

 In the Gray Herbarium is a sheet of this number without the cones 

 to supply the crucial evidence whether this is the "limber pine" or 

 the nearly related P. alhicaulis. A specimen collected by Lemmon 

 on Mt. Tallac and referred to P. flexilis is certainly the other species. 



3. Pinus albicaulis Engelm., Trans. St. Louis Acad., vol. 2, p. 209. 



1863. 



P. flexilis var. alhicaulis Engelm., Bot. Calif., vol. 2, p. 12-i. 1880. 

 P. cembroidcs Newberry, Pac. K.R. Rej^t., vol. 6, Bot., p. 44. 1857. 

 Ainnus flexilis Eydb., Bull. Torr. Bot. Club, vol. 32, p. 598. 1905. 



Type locality. — "Passes of the Cascade mountains, about latitude 

 44° north." 



