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trees or shrubs belonging to the division Taxaceæ of the order Coniferæ. Bark reddish or reddish brown, thin and scaly. Branches spreading, giving off branchlets, of one kind only, irregularly alternate, surrounded at their bases by brownish scales. Buds globular or ovoid, of imbricated scales. Leaves inserted on the branchlets in a spiral order, on upright shoots spreading radially, on horizontal shoots disposed by twisting on their petioles in one plane in a pectinate arrangement, the upper and lower leaves being of the same length, with their dorsal surfaces turned upwards and their ventral surfaces downwards. In fastigiate varieties all, or most, of the branchlets assume an erect position, and the leaves in consequence are arranged radially. The leaves are linear, flat, with recurved margins, dark green above, paler green below; the lower surface only bearing stomata, which never form conspicuous white bands; narrowed at the base into a short petiole, arising from a linear cushion on the twig; mucronate or acute at the apex and without a resin-canal.

Flowers diœcious, or in rare individuals monœcious, on the under surface of the branchlets of the preceding year, in the axils of the leaves, the female flowers being less numerous than the male flowers. Male flowers composed of a stalk, girt at its base by imbricated scales, and bearing above a globose head of 6–14 stamens with short filaments. The stamen is expanded above into a peltate connective, which bears on its lower surface 5 to 9 pollen sacs, united with each other and with the filament. The female flowering shoot, arising out of the axil of the leaf, is composed of a number of imbricated scales, in the axil of the uppermost one of which is borne an ovule, placed so close to the apex of the shoot as to appear terminal; in the scale next below a bud occurs, which occasionally develops into a second ovule. The ovule, which has a small membranous disc at its base, projects out of the scales by its micropyle. Seed sessile in a fleshy, juicy cup, forming an aril (the enlarged disc), open at the top and free from the seed in its upper part. The seed variable in form, 2, 3, or 4-angled, is generally ellipsoid and has a ligneous testa, containing oily white albumen, in the upper part of which is an axile straight cylindrical minute embryo with two cotyledons.

Yews differ from all other Coniferæ in the character of the fruit. They