78 JOUHN.VL OF THE ARNOLD ARBORETUM [vol. i 



pubescence of grayish and fulvous hairs. From Churchill is also E. A. & 

 A. E. Preble's No. 23, st.; W. which looks rather typical In other frag- 

 ments brought by J. W. Tyrull from the region between Athabasca and 

 Chesterfield Inlet, August 11, 1893 (No. 1763^, O; fr. juv.) and September 1, 

 1893 (No. 1763^\ O.; fr.) the pubescence of the twigs is less developed and 

 the leaves are even more narrowly lanceolate. Seton & Preble collected a 

 specimen in the region of Great Slave Lakennd near Stone Island, July 14, 

 1907 (No. 37 [ = 78399,0], fr.). It has larger aments (up to 5.5:3 cm.), iu\d 

 the fruits are about 7 mm. long with a style 1 mm. In length. Another 

 specimen is A. E. Preble's from Fort Kesolution, July 14, 1901 (No. 143, st.; 

 Vs\), The same collector brought some more specimens from the Mackenzie 

 River in 1904. One, collected at Fort Norman, June 12 (No. 322^, fr. im.; 

 W.), has half-developed young leaves without any stomata in their upi)er 

 ej>idermis and no trace of stipules. It looks like typical S. planifolia, Tlie 

 others came from Fort Simpson, May 12 (No. 303^'. f; W.) and May 15 

 (No. 305, m. and st., with very young leaves; W.) In the male flowers the 

 bracts are acute, otherwise there seems to be no difference between the last 

 two numbers and No. 322^. I have susi)ected that S. pulchra might grow 

 in this region, but I have not yet seen specimens of it from tlie Northwest 

 Territories exce])t very poor and uncertain fragments mentioned under 

 S. pulchra on p. 71, which after all may be referable to S. planijolia; but the 

 Mackenzie region is, probably, the meeting ground of these species. 



It is possible that typical S. planijolia also occurs in the northern Rocky 

 Mountains from Alberta to northern Wyoming. On the otlier hand the 

 western form hereto referred to 8. chlorophylla seems to represent a distinct 

 variety. The name S. chlorophylla cannot be used, and the majority of the 

 western specimens before me (I havea well collected representative series at 

 hand) are most closely related to S. monica Bebb, This species is nothing 

 but the dwarfed high alpine form of this western variety for which I pro- 

 pose the name. 



4b. S. planifolia var, monica, nov. var. — S. monica Bebb in Watson, 

 Bot. Cal. II. 90 (1879); in Bot. Gaz. xvi. 107 (1891). — Ball in Trans. 

 Acad. Sci. St. Louis, ix. 84 (1899). — Jepson, Fl. Cal. i. 344 (19Q9), pro 

 parte, — Hall, Yosem. Fl. 69 (1902), prob. tantum pro parte. — S. chloro- 

 phylla Bebb^ m Coulter, Man. Rocky Mts. Bot. 337 (1885). — Porter & 

 Coulter hi U.S. Gcol. Surv. Misc. Publ. no. 4. 128 (Syn. Fl. Colo.) (1874). 

 Macoun, Cat. Can. Tl. i. 446 (1886), pro parte. — Nelson in Bull. Wyo. 

 Exp. Sta. XXVIII. 179 (1st Rep. Fl. Wyo.) (1886). — Ball in Trans. Acad. 

 Sci. St. Louis, IX. 83 (1899), excl. syn.; in Coulter & Nelson, New Man. 

 Rocky Mts. Bot. 137 (1909). — Rydberg, Fl. Colo. 96 (1906); FL Rocky 

 Mts. 198 (1917). — Daniels in Univ. Mo. Stud. Sci. Ser. ii. 248 (Fl. Boulder, 



Colo. 100) (1911). 



Bebb described his species from "poor stunted specimens" collected by 

 Bolander at Mono Pass Summit. The real collector was probably W. H. 



1 Belib and the following authors also inchide the forms of the northern Rookies which, as 

 I have already stated, may, at least partly, be referable to the typical eastern S. planifolia. 



