fourteen to fifteen scales. Scales thin, broader than long, semicircular with a wedge-shaped base, convex, margin irregularly denticulate, pubescent on both surfaces. Bract oblong, abruptly tapering at the apex, which is visible between the scales. Seed with terminal asymmetrical wing, and two resin-vesicles on the side next the scale.
The name Pattoniana is adopted as being the first published under the correct genus Tsuga. The tree is known to American botanists as Tsuga Mertensiana, which is unfortunate, as this name was for many years in use for the western hemlock. There is no confusion possible if Pattoniana be selected, as no other hemlock has been known at any time by this name.
Varieties
The preceding description is drawn up from living specimens of the form with bluish entire leaves, cultivated in this country, and applies, in all essential characters, to dried specimens from trees growing wild in America. I have examined the material in the Kew herbarium and also specimens collected by Elwes on Mount Shasta at 7500 feet elevation; and there do not appear to be two distinct varieties of the tree in the wild state, as the presumed alpine form is only a stunted shrub which agrees in botanical characters with the trees from lower levels.
In England, however, there is a form in cultivation, distinguished by its green serrulate leaves, which differs in many respects from the other form. Concerning its origin, we only know, on the authority of Murray,[1] that it was raised at Edinburgh from seeds collected by Jeffrey in 1851 on the Mount Baker range in British Columbia. Jeffrey found trees growing there from 5000 feet elevation to the snow line, varying in size from 150 feet in height and 13½ feet in girth at lower levels to a stunted shrub not more than 4 feet high close to the timber line. Specimens at Kew from Mount Baker gathered by Jeffrey all have entire leaves and belong to the ordinary wild form.
Engelmann,[2] who visited the Mount Baker range, states that the trees growing there are the ordinary forms of Tsuga Pattoniana and Tsuga Albertiana. He suggests that the plants raised from Jeffrey's seed may be a mountain form of the latter species; but this cannot be admitted, as they do not resemble that species in botanical characters (buds, leaves, etc.). It is possible that these plants are only a seedling variation of Tsuga Pattoniana, and do not correspond with any distinct species or geographical form in the wild state.
Murray,[3] believing that he had two species to deal with, named the bluish form Abies Hookeriana, and assigned the name Abies Pattoniana, Balfour, to the other form. The original figure of Balfour's species represents, however, the same plant as Abies Hookeriana of Murray; and much confusion has resulted in consequence in the use of the two names Hookeriana and Pattoniana. It is most convenient to
- ↑ Edin. New. Phil. Jour. 289 (1855) and Proc. Hort. Soc. ii. 202 (1863).
- ↑ Gard. Chron. xvii. 145 (1882).
- ↑ The distinctions relied on by Murray in the cones are trifling; and in the Kew Herbarium there are wild specimens showing these differences, but all belonging to the form with blue entire leaves. I have not seen cones belonging to the other form.
