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JOURNAL OF THE ARN'OLD ARBORETUM [vol. i 



No. 470, Colorado, mountains northwest of Boreas, Summit County, moun- 

 tain slopes near timber line, about 8,500 m., August 2, 1895 (f., fr. juv.; N., 

 W.), and (". L. Shear's No. 4^280, Ui. Blanca, Costilla County, about 4;)()0 

 m., July 31, 1900 (fr. ; N., ^Y; "spreadin^r, 2 ft. higir')- They gradually 

 pass into the more vigorous forms with stouter aments and larger leaves 

 which have more or less numerous slomata in the epidermis of the u])i)er 

 surface until we come to forms in Wyoming (like Albany County, August 

 23, 1904, F. V. Cnville, No. 2070, fr.; W.) and in Alberta (Calgary, June 5, 

 1897, J. Macoun, No. 94427, O., fr.; stomata in pagina superiora non visa; 

 and Jumping Tound Creek, Jime 12, 1897, ./. i\racou7i, No. 94425, O., si; 

 nuigis intermedia inter var. Iijpicam et var. montcam videtur) which I am 

 at a loss how to distinguish from certain forms of the White Mountains, 

 New Hampshire. A vigorous western specimen does not look more differ- 

 ent from the typical dwarf liigh alpine var. mouicn than an eastern sj)cci- 

 men, grown in a i)rotected situation in the Great Gulf on Mt. Wasliington, 

 diverges in habit, etc., from the "depressed and prostrate shrul), seldom ris- 

 ing more than one foot from the ground" (Faxon) in exposed situations of 

 the Alinne Garden on the same mountain, where I had an oi)portunity to 

 observe it myself in September 1918. Tlierefore, 1 leave it, at present, an 

 open (piestion where the line can be drawn between Hie range of the ty])e 

 and var. monica. I have seen specimens which I refer (partly only provi- 

 sionally) to this variety from California (Mono and Tuolunme Counties), 

 Utah (Salt Lake, Wasatch, Duchesne or Summit, and Sevier Counties), 

 New Mexico (Mora County), Colorado (through the Rockies from Costilla 

 to Larimer County), Wyoming (Albany, Fremont, Sheridan Counties, and 

 Yellowstone Park), Montana (:\Lidison and Fark Counties), to All)erla 

 (see above). There is a specimen sajd to have come from the "interior of 

 Washington Territory," 1841, C. I. Fidceritig d- ]V. 0. Brcckcnr'uhjc (Wilke's 

 Exped. No. 481, f.; N., W.) which had been in 1900 named N. ddorophijlla 

 by Ball (W.) who in 1915 cites it under his S. pcrnwia. Judging l>y Piper's 

 remarks (Fl. Wash. 15) as to the labeling of this collection il seems that the 

 locality is not correct. It does not look to me like S. pcntiafa l)ut is ex- 

 tremely alike var. monica sensu meo. While on the other hand, the cJdoro- 

 phylla mentioned by Bebb (18<)1) as occurring "on Mt. Adams and the 

 higher summits of the Cascades" is N. pennaia. 



In 1905 (Bot. Gaz. xl. 379, t. 13, figs. 8-11) Ball described a S'. Selsonil 

 the type of which was collected l)y A. Nelson on Laramie Peak, Albany 

 County, Wyoming, along creek, July 13, 1890 (No. 7580, fr.; L.). Professor 

 A. Nelson has kindly loaned me all the material from Herb. L. I a'so have 

 had an opportunity to discuss this plant with Mr. Ball, who tells me 

 that he is now inclined to believe that S. Nehonii is nothing but a form 

 of S. chhrophyUa ( = S. pkmifolia). In his renuirks with the original 

 description Ball said that S. Xilsottii "is most closely related to ^'. chloro- 

 phylla' but that "it is readily distinguished by the oblanceolale leaves 

 which, when nuiture, are j)roniineutIy nerved above and reticidated be- 

 neath." In his treatment of the Rocky INIountain Willows (apud Coulter & 



