CONIFERS. 8ILVA OF NORTH AMERICA. 95 



ABIES. 



Flowers solitary, naked, monoecious, axillary ; stamens indefinite, anther-cells 2, 

 surmounted by short knobs ; scales of the pistillate flowers spirally disposed, ovules 2 

 under each scale. Fruit an erect strobile maturing in one season, its scales longer or 

 shorter than their bracts, deciduous from the central axis ; seeds furnished with resin 

 vescicles. Leaves subdistichous, persistent. 



Abies, Linnseas, Gen. 294 (in part) (1737). — Adanson, Pinus, Linnaeus, Gen, ed. 6,434 (in part) (1754). — End- 



Fam. PL ii. 480 (in part). — A. L. de Jussieu, Gen. 414 liclier, Gen. 260 (in part). — D. Don, Lambert Pinus^ iii. 



(in part). — Link, Ahhand. Alcad. Berl. 1827, 181 ; iira- (sect. Pence), — Meissner, Gen. 352 (in part). — Baillon, 



ncea, xv. 525. — Engelmann, Trans. St. Louis Acad, ii. Hist. PL xii. 44 (in part). 



211 ; iii. 593. — Bentham & Hooker, Gen. iii. 441. — Picea, Loudon, Arb. Brit. iv. 2329 (not Link) (1838). 

 Eichler, Mngler & Prantl Pflanzenfam. ii. pt. i. 81. 

 Masters, Jour. Linn. Soc. xxx. 34. 



Tall pyramidal trees, with bark containing numerous prominent resin vesicles, and often thick and 

 deeply furrowed in old age, pale usually brittle not durable wood, slender horizontal wide-spreading 

 branches in regular remote generally four or five-branched whorls or rarely scattered, furnished with 

 twice or thrice forked lateral branches forming flat-topped masses of foliage gradually narrowed from 

 the base to the apex of the branch, the ultimate divisions comparatively stout, glabrous or pubescent, at 



+ 



right angles to the branch or pointing forward, wide-spreading roots, and slender elongated rootlets. 

 Branch-buds usually three, or on the leading shoot four or five, the lateral in the axils of upper leaves, 

 and much smaller than the terminal, generally thickly coated with resin, small, subglobose or oblong, 

 acute or obtuse, or rarely large and acute, covered with numerous ovate acute closely imbricated 

 accrescent rarely stomatlferous * scales increasing in size from below, the two lowest minute, opposite and 

 lateral, the outer persistent on the base of the branch and In falling marking It with ring-like scars, the 

 inner occasionally united and deciduous In one piece from the tip of the lengthening branchlet.^ Leaves 

 spirally disposed, incurved in the bud, at first densely crowded on the young branchlets, lanceolate or 

 oblanceolate, entire and often thickened and revolute on the margins, sessile, marked on the lower 

 surface on each side of the midrib with bands of several rows of stomata, persistent usually for from 

 eight to ten years, leaving in falling nearly circular scars 5 hypoderm cells large, in continuous or 

 interrupted bands under the epidermis on the upper surface, usually present also on the edges and keel 

 of the leaf and in some species in its interior ; resin ducts two, close to the epidermis of the lower 

 surface, generally near the edge of the leaf, or in some species in the parenchyma and almost equidistant 

 from the two surfaces; fibro-vascular bundles usually two or rarely one, occupying the interior of the 

 leaf ; on young plants and on lower sterile branches leaves flattened and mostly grooved on the upper 

 surface, or in one species nearly tetragonal, rounded and usually emarginate at the apex, appearing two- 

 ranked from a twist near their base or occasionally spreading from all sides of the branch, only rarely 

 stomatlferous on the upper surface ; usually on upper fertile branches and leading shoots crowded more 

 or less erect, often incurved or falcate, thick, convex on the upper side, or quadrangular in some species 

 obtuse or acute at the apex, and frequently stomatlferous on the upper surface ; often crowded arcuate 

 and forming a thick cover over the winter-buds on the ends of leading shoots and branches.^ Flowers 

 axillary, surrounded at the base by conspicuous involucres of their accrescent bud-scales, the Inner often 

 much enlarged and white and lustrous, appearing in early spring from buds formed the previous summer 

 on branchlets of the year 5 the staminate on their lower side, very abundant on branches above the 



