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Rh apply the name Pattoniana to the bluish form, as it is the earliest name of the wild plant, and to consider the green-foliaged plant to be a variety of it, which may be called var. Jeffreyi.

The two forms are distinguished as follows:—

1. Var. typica. The form distinguished in cultivation by its bluish foliage. Introduced in 1854 by William Murray, who found the tree on Scots Mountain, in California.

Leaves, though radially arranged, tending on the lower side of the shoot to be in the plane of the branch and not spreading; those on the upper side of the shoot curved and directed outwards and forwards. They are long and narrow, $1/2$ to $7/8$ inch long, and $1/20$ inch wide, entire in margin, convex on both surfaces, the groove in the median line above being very short or absent and never continued to the apex of the leaf, which is rounded or acute; both surfaces marked with conspicuous lines of stomata extending from the base to the apex of the leaf.

2. Var. Jeffreyi. Only known in cultivation, distinguished by its greenish foliage.

Leaves spreading radially and directed outwards (never forwards) on all sides of the shoot; straight, short, and broad, less than $1/2$ inch long and about $1/16$ inch in width, serrulate in margin; upper surface flattened and distinctly grooved, the groove continued to the rounded apex; lower surface convex, with lines of stomata the whole length of the leaf. On the upper surface the stomata only occur in four to six broken lines towards the apex.

This form agrees with the typical form in the character of the buds and pubescence of the branchlets; the shoots, however, are not so slender.

Mr. Gorman gives the following account of the supposed Alpine form, alluded to above:—"Among the hardy alpine trees Hooker's hemlock stands pre-eminent, having a northern range far beyond that of even the white-barked pine. It is a small, dwarfed and stunted tree compared with the type, and seldom exceeds 12 inches diameter or 30 feet in height. It usually ranges in altitude from 5500 to 6400 feet, but is occasionally found up to and beyond 7000 feet where it can find sufficient moisture. Though generally favouring the heads of moist valleys it is sometimes to be found on the leeward side of peaks and slopes, where snowbanks of sufficient size have formed in winter to maintain an adequate supply of moisture during the rest of the year. It is in the latter situations where the tree reaches its highest altitude. In addition to its smaller size and more alpine habit it further differs from its nearest congener in having thinner bark and small erect cones, all the other hemlocks having pendent cones. The tree is too small and inaccessible to have any economic value."

This seems to be distinguished principally by its erect cones. Sargent, who alludes to Gorman's account, does not consider this variation to be worthy of distinc-