ENUMERATION OF CONIFERS 269 



7. T. Mertensiana, Sarg., not Carr. {T. Pattoniana, Senecl. T.HooJceriana, 

 Carr. T. Roczlii, Carr. Abies Williamsonii, Newb. Ilesperopeuce Pat- 

 toniana, Lemm.). Mountain H. Tree attaining 100 and occasionally 150 

 feet, with slender pendent branches usually forming an open pyramid; 

 winter-buds ovoid, acute; young branclilets light reddish-brown, pubescent, 

 usually short and upright: leaves spirally arranged around the branches, 

 linear, usually curved, acutish, mostly rounded or keeled, rarely slightly 

 grooved above, light bluish-green or pale bluish-white, with whitish lines 

 on both sides, 3^-1 inch long: cones cylindric-oblong, usually violet-purple 

 before maturity, brown when ripe, 2-3 inches long; scales obovate, puberu- 

 lous outside. Southern Alaska to northern Montana, Idaho, and California. 

 —Introduced to Great Britain in 1851 by Jeffrey. Hardy in sheltered posi- 

 tions as far north as Massachusetts, rarely cultivated in the Eastern States. 

 To avoid confusion one has to bear in mind that T. hcterophylla was known 

 for a long time as T. Mertensiana and still bears this name in many gardens. 



Var. argentea, Sudw. With bluish-white foliage. 



A supposed hybrid of this and the preceding species is T. Jefifreyi, Henry 

 {T. Mertensiana var. Jeffrcyi, Schneid.). Buds ovoid, acute: leaves radially 

 spreading and directed outward, green and grooved above with a few broken 

 lines of stomata near apex, finely serrulate. — Originated from seed of T. 

 Mertensiana introduced in 1851 by Jeffrey. 



24. PICEA, A. Dietr. SPRUCE 



Evergreen pyramidal trees with usually whorled branches and with scaly 

 bark; branchlets with prominent leaf -cushions (pulvini) separated by incised 

 grooves and produced at the apex into a peg-like stalk bearing the leaf: 

 leaves usually 4-angled, with white lines formed by numerous stomata 

 arranged in rows on all four sides, or compressed and stomatiferous only on 

 the upper or ventral side which, on the lateral branchlets, by twisting of the 

 leaf-stalk appears to be the lower one, sessile and jointed at the base to a 

 short stalk-like projection (sterigma) of the pulvinus: flowers monoecious, 

 catkin-like, terminal or axillary; the staminate j^ellow or red, consisting of 

 numerous spirally arranged anthers with the connective enlarged at the apex 

 and scale-like; the fertile ones greenish or purple, consisting of spirallj' ar- 

 ranged scales each subtended at the base by a small bract and bearing 2 ovules 

 at the inner side: cones pendulous or spreading, with persistent scales not 

 separating from the axis after shedding the seeds, which are provided with a 

 large and thin obovate or oblong wing; cotyledons 4-15. (Picea is the ancient 

 Latin name of the spruce, derived from fix, pitch.) — Thirty-eight species 

 in the colder and temperate climates of the northern hemisphere from the 

 arctic circle to the high mountains of the warm-temperate regions. They are 



