Trees deciduous, dioecious; trunk tall, densely branched; branchlets dimorphic: both long and short. Leaves sparsely and spirally arranged on long branchlets, fasciculate on short branchlets, long petiolate, flabellate, venation parallel, close, dichotomous, open but with rare anastomoses, base broadly cuneate, margin straight, entire, apex 2-lobed or notched. Reproductive structures produced in clusters in axils of scalelike leaves at apex of short branchlets before leaves expand. Pollen cones pedunculate, pendulous, catkinlike; microsporophylls numerous, spirally and rather sparsely arranged; microsporangia 2, elliptic; pollen sacs longitudinally dehiscent. Ovules borne on a long, dichotomously branched peduncle sometimes dividing into 3-5 terminal forks; each fork discoid at apex, bearing an erect, sessile ovule; usually only 1 seed ripening per peduncle. Seeds long pedunculate, pendulous, drupelike, with a single integument differentiated into a fleshy, succulent sarcotesta, a bony sclerotesta, and a membranous endotesta; female gametophyte tissue abundant. Cotyledons 2(or 3). Germination hypogeal. 2n = 24*.
Trees , deciduous, dioecious (possibly rarely monoecious). Bark gray, furrowed, with flattened ridges. Long shoots and short (spur) shoots present. Roots fibrous to woody. Leaves simple, alternate to fascicled, stomates abaxial; apices deeply cleft to truncate; petioles equal to or exceeding blades; resin canals absent. Pollen cones borne on spurs, catkinlike; sporophylls distributed along axis; bracts absent; pollen spheric, not winged. Seed cones absent; ovules 2, pedunculate, subtended by collar believed to comprise 2 modified megasporophylls, borne on spurs. Seeds with fleshy outer coat, inner coat hard; cotyledons 2--3.
Page, C. N. 1990. Coniferophytina: Ginkgoaceae. In: K. Kubitzki et al., eds. 1990+. The Families and Genera of Vascular Plants. 1+ vol. Berlin etc. Vol. 1, pp. 284--289.
|Maidenhair Tree Family|