THE CONIFERS. The distinguishing feature of this great tree group is the cone-bearing habit. The overlapping scales of the cone are at tached to a central stem, and each scale bears one or more naked ovules when the time of flowering comes. Pollen from the staminate flowers falls on the exposed ovules, fertilising them, and thus seed is set. The fertile scales are favourably situated near the middle of the cone. Here the best seeds are found. The terminal scales crowd at both ends of the cone, and their seeds usually fail utterly or are stunted in development.
The coalescence of scales to form soft berries characterises the junipers, but the cone-like flowers indicate that the modification h fruit is more apparent than real. The scale tips are there on the outside of the berry to indicate the close kinship of these trees with other conifers.
The yews are not conifers, but are set in a family by them selves. A single ovule stands erect in the pistillate flower, and becomes in fruit a i-seeded drupe, or soft berry. Two genera of yews, with two species of trees in each, constitute the family in. the United States. The conifers include thirteen genera and a great number of species, quite overshadowing the yews in im portance. Together the two families form the botanical grand division of the Gymnosperms, resinous plants (mostly trees) whose flowers have no true pistils, but bear their ovules naked— on a cone scale in the conifers—without even a scale to lean upon in the yews.
The Ginkgo or Maidenhair Tree (Salisliria of Japan and China, is a tree whose botanical affinities seem to be with the conifers on one side and the ferns on the other. The leaves are fan-shaped, usually cleft with one deep suture to the petiole. The venation is the strange character. Unbranched veins extend in radiating lines to the upper border of the fan, just as in the leaf of maidenhair fern. The texture is leathery, and the leaves are fascicled on the ends of very short side twigs. Bright yellow green in summer, they turn to gold, and fall in the autumn.
The ginkgo is a narrow, tapering tree when young, very [rim and pretty, widening to pyramidal form with years. It grows
rapidly and has been planted as a street tree, notably in Wash ington, D. C. A serious drawback appears in the fruit, which is a soft, plum-like, oily drupe with an unpleasant odour. While they are dropping they keep sidewalks in a bad state, disgusting people with the tree. The ginkgo has had a great vogue among planters, though until recently none have been old enough to bear fruit.
The Chinese esteem the pits a great delicacy. They roast the nuts as we do almonds and use them as a confection or an appetiser at dinners and banquets.
KeY TO THE GENERA A. Fruit a woody cone.
B. Cone scales each in axil of a bract; seeds 2, inverted, on each scale.
C. Foliage needle-like, fascicled.
D. Cones requiring 2 to 3 years to mature; leaves evergreen, 1 to 5 in papery basal sheath.
Genus PINUS, THE PINES DD. Cones annual; leaves deciduous.
Genus LARIX, THE LARCHES CC. Foliage linear, solitary, scattered.
D. Leaves flat, borne on short petioles ; cones pendant.
E. Twigs set with projecting leaf bases.
Genus I SUGA, THE HEMLOCKS EE. Twigs smooth.
Genus PSEUDOTSUGA, THE DOUGLAS SPRUCE DD. Leaves 4-angled, or flattened, without petioles. E. Twigs rough; cones pendant.
Genus PICEA, THE SPRUCES EE. Twigs smooth; cones erect.
Genus ABIES, THE FIRS BB. Cone scales without bracts.
C, Leaves linear, alternate; cone scales many.
D. Seeds many under each scale; leaves evergreen.
Genus SEQUOIA, THE SEQUOIAS DD. Seeds 2 under each scale; leaves 2-ranked, decidu ous. Genus TA XODIUM, THE BALD CYPRESS CC. Leaves scale-like, usually of two forms; cones small. D. Cones elongated, thin scaled, annual, with 2 seeds under each scale.
E. Scales of cone 6; seed wings unsymmetrical. Genus LIBOCEDRUS, THE INCENSE CEDAR EE. Scales of cone 8 to 12; seed wings symmetrical. Genus THUYA, THE ARBOR VIDES DD. Cones globular, thick scaled.
E. Seeds many under each scale; cones biennial. Genus CUPRESSUS, THE CYPRESSES EE. Seeds 2 under each scale; cones annual.
Genus CHAM/ECYPARIS, THE CyPRESSES AA. Fruit a berry; by union of scales of the flower; leaves scale-like or awl shaped, 3 to 4 ranked.
Genus JUNIPERUS,,THE JUNIPERS