122 



SILVA OF NORTH AMERICA. 



CONIFERJE. 



from one eighth to one quarter of an inch thick, very resinous and covered by orange-brown scales, 

 those of the inner ranks being united into a cup-like cover on the lengthening branchlet and falling 

 in one piece. The branchlets are glabrous, lustrous, and comparatively stout; during their first season 

 they are dark orange-color, and, becoming light grayish green or pale reddish brown during their second 

 season, they gradually turn gray or grayish brown. The leaves are crowded, distichously spreading, and 

 more or less erect even on the lower branches of young trees from the strong twisting of their base, and 

 are pale blue or glaucous, becoming dull green at the end of two or three years, marked on the lower 

 surface by two broad bands each of from six to eight rows of stomata, and more or less stomatiferous 

 on the upper surface, their hypoderm cells forming an interrupted layer under the epidermis on the 

 upper side ; on lower branches they are flat, straight, rounded, acute, or acuminate at the apex, from 

 two to three inches in length and about a sixteenth of an inch wide, and on fertile branches and on 

 old trees they are frequently thick, keeled on the upper surface, usually falcate, acute or rarely notched 



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at the apex, from three quarters of an inch to an inch and a half long and often fully an eighth of 

 an inch wide.^ The staminate flowers are oblong-cylindrical and from one half to three quarters of 

 an inch long, with dark red or rose-colored anthers which turn yellow in fading; the pistillate flowers 

 are cylindrical, and from an inch and a quarter to an inch and a half long, with broad rounded scales 

 and oblong strongly reflexed oblong-obcordate bracts laciniate above the middle and abruptly contracted 

 at the apex into short points. The cones are oblong, slightly narrowed from near the middle to the 

 ends, and rounded and retuse at the apex, from three to five inches long, from an inch and one 

 quarter to an inch and three quarters thick, puberulous, and grayish green, dark purple,^ or bright 

 canary-yellow, with scales which are much broader than they are long, gradually and regularly 

 narrowed at the denticulate sides from the rounded apex, and rather more than twice the length of 

 their bracts ; these are oblong, emarginate or nearly truncate and denticulate at the broad apex, 

 which terminates in a short slender mucro. The seeds are from one third to nearly one half of an 



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inch in length, very acute at the base and dark dull brown, with lustrous bright rose-colored wings 

 which are widest near the middle, about one third longer than they are broad, and nearly truncate at 

 the apex. 



Of the Fir-trees of North America, AMes eoneolor best endures heat and dryness, and it is 



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able to grow on arid mountain slopes where few other trees can maintain a foothold. Its northern 

 home is on the Cascade Mountains of southern Oregon.* It is common on the Siskiyou and other 



^ The leaves of Abies ' eoneolor are usually rounded and only 

 exceptionally notched at the apex, but in dry regions they are often 

 acute or acuminate, and are sometimes furnished with stiff callous 

 tips. In California, on the San Kafael Mountains, some of the 

 leaves of this tree are acute ; on the San Bernardino Mountains fer- 

 tile branches bear acute leaves nearly an inch and a half long, 

 terminating in long callous tips, and such leaves are also produced 

 on trees growing on the San Francisco Peaks of Arizona, and ou 

 the Huachuca Mountains of southern Arizona, and near Santa F^ 



be depended on to furnish constant specific characters, as English 

 botanists have sometimes believed, for the separation of this White 

 Fir into two species. Although trees east of the Sierra Nevada 

 usually bear longer and more pointed leaves than those which grow 

 on the western slope of the Sierras (the Ahies Lowiana of English 

 gardens, see Masters, Gard. Chron. n. ser. xxvi. 755, f. 14G~148), 

 I have gathered specimens in Strawberry Valley, in northern Cali- 

 fornia, with acute leaves, and such leaves may be found all through 

 the Sierras, while in Colorado and New Mexico trees with leaves 



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in New Mexico. On the upper slopes of the southern rim of the obtusely rounded at the apex are common. 



Grand Canon of the Colorado in Arizona, Ahies eoneolor sometimes 

 produces very flat thin strongly falcate leaves gradually narrowed 

 into slender callous-tipped points ; and on San Pedro Martir, in 

 Lower California, its leaves are very thick and rigid, with prominent 

 midribs on the upper side, strongly falcate, acute or acuminate, with 

 callous tips, from an inch to an inch and a half long and rather 

 more than an eighth of an inch wide. In Colorado and New 

 Mexico the leaves, especially on young trees, are usually but not 

 always of a more glaucous color than farther westward, but the 

 color of the leaves can hardly be relied on to separate specifically 

 the tree of the California Sierras from that of the interior any 



2 Brandegee, Bot Gazette, iii. 33. 



s In southern Oregon Abies eoneolor is very abundant on low 

 hills at elevations of between two and three thousand feet above 

 the level of the sea. Although I have not seen it north of a line 

 drawn from Ashford on the west to Upper Klamath Lake, on the 

 east of the Cascade Mountains, Ahies eoneolor will probably be^ 

 found west of the Cascade Mountains as far north as the divide 

 between the waters of the Umqua and Rogue Rivers, which, mark- 

 ing the southern limits of distribution of many northern plants and 

 the northern limit of many from the south, is the real northern 

 boundary of the region occupied by the California flora. Speci- 



more than the length of the leaves and the form of their apex can mens gathered by Coville in 1897 at Fish Lake, which is one of 



