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trees with aromatic odour, belonging to the tribe Cupressineæ of the order Coniferæ, closely resembling Thuya in habit and other characters, the branches as in that genus ending in frondose "branch-systems,” which are flattened in one plane and three- to four-pinnately divided, with their axes bearing scale-like leaves in four ranks. On the main axes the leaves are often remote by the lengthening of the nodes ; on the lateral axes they are closely imbricated, and vary in the different species in size and form, as detailed in the three sections below. In seedling plants the leaves are always linear-lanceolate and spreading.

Flowers: monœcious with those of the two sexes on different branchlets, or rarely dicecious, solitary, terminal. Male flowers oblong, subsessile, with six to twenty stamens decussately opposite on a slender axis; filaments short, dilated into broadly ovate or orbicular scale-like peltate connectives, which bear usually four sub-globose anther-cells, two-valved and opening on the back. Female flowers oblong; subtended at the base by several pairs of leaf-like scales, which persist slightly enlarged under the fruit; composed of four or six decussately opposite acuminate bracts; lowest pair small, unfertile; next pair above fertile, bearing at the base two erect ovules on a minute accrescent ovular scale ; uppermost pair when present unfertile.

Cones small, pendulous or erect, ripening and letting out the seed in the first year, persistent empty on the branchlets in the second year. Scales decussate, four or six; the lowermost pair short, thin, often reflexed ; the next pair long, thickened, woody, widely spreading at maturity, marked externally close to the apex by the shortly acuminate or long-beaked tip of the bract; third pair, when present, con- nate into an erect median partition. Seeds, two or one by abortion on each of the two fertile scales, with two lateral wings, one broad, oblique, nearly as long as the scale ; the other short, narrow, or rudimentary; cotyledons two.

Eight species of Libocedrus have been described, remarkable for their distribu- tion over widely separated areas in the two hemispheres. Three sections may be distinguished :—