Pseudophœnix (p. 109). Stem simple or branched; leaves sessile, lanceolate, long- and usually sharp-pointed at apex. Yucca (p. 110). II. Leaves 1-nerved, needle-shaped, linear or scale-like, persistent (deciduous in Larix and Taxodium). Gymnospermæ. 1. Leaves Persistent. _a_ Leaves fascicled, needle-shaped, in 1—5-leafed clusters enclosed at base in a membranaceous sheath. Pinus (p. 2). _aa_ Leaves scattered, usually linear. _b_ Leaves linear, often obtuse or emarginate. Base of the leaves persistent on the branches. Leaves sessile, 4-sided, or flattened and stomatiferous above. Picea (p. 34). Leaves stalked, flattened and stomatiferous below, or angular, often appearing 2-ranked. Tsuga (p. 42). Base of the leaves not persistent on the branches; leaves often appearing 2-ranked. Leaves stalked, flattened, stomatiferous below; winter-buds pointed, not resinous. Pseudotsuga (p. 47). Leaves sessile, flattened and often grooved on the upper side, or quadrangular, rarely stomatiferous above, on upper fertile branches often crowded; winter-buds obtuse, resinous (_except in No. 9_). Abies (p. 50). _bb_ Leaves linear-lanceolate, rigid, acuminate, spirally disposed, appearing 2-ranked by a twist in the petiole. Leaves abruptly contracted at base, long-pointed, with pale bands of stomata on the lower surface on each side of the midveins; fruit drupe-like. Torreya (p. 91). Leaves gradually narrowed at base, short-pointed, paler, and without distinct bands of stomata on the lower surface; fruit berry-like. Taxus (p. 93). _bbb_ Leaves ovate-lanceolate and scale-like, spreading in 2 ranks or linear on the same tree, acute, compressed, keeled on the back and closely appressed or spreading at apex. Sequoia (p. 61). _aaa_ Leaves opposite or whorled, usually scale-like.