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Pinaceae (order Coniferales) A family of conifers that bear both male and female cones and in which the seeds are borne between the cone scales, with no fleshy arils. The leaves are spirally arranged and linear. The cone scales are arranged spirally, each scale in female cones being a double structure with the ovule-bearing scale borne in the axil of a bract that is fused to it only at the base. Female cone scales each bear 2 inverted ovules on their upper surfaces. Male cone scales each bear 2 pollen sacs on their lower surfaces, containing pollen grains each with (usually) 2 bladder-like sacs. There are 9 genera, comprising 194 species, occurring in the northern hemisphere, mainly in temperate climates.