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The cone of Pinophyta (conifer clade) contains the reproductive structures. The woody cone is the female cone, which produces seeds. The male cone, which produces pollen, is usually ephemeral and much less conspicuous even at full maturity. The name "cone" derives from Greek konos (pine cone), which also gave name to the geometric cone.
The male flower head may be yellow or burgundy red, is cone- or egg-shaped, 8–19 cm (3.1–7.5 in) long, hardly about 1 + 1 ⁄ 4 cm (0.49 in) across, subtended by an involucre of several leaves of about 1.9 cm (0.75 in) long that are often covered in rusty-coloured soft hairs.
The female cone then opens, releasing the seeds which grow to a young seedling. To fertilize the ovum, the male cone releases pollen that is carried in the wind to the female cone. This is pollination. (Male and female cones usually occur on the same plant.) The pollen fertilizes the female gamete (located in the female cone).
The cones are sexually dimorphic: the male cone is a 40 to 50 cm long cylinder that is 7 to 10 cm wide with a peduncle that is up to 2 to 3 cm long; the female cone is 25 to 50 cm long, 20 to 25 cm wide, and sessile. Males can have up to ten cones at one time and females can have up to five cones at one time. [3]
Cross section of Williamsonia harrisiana (India, Jurassic - Early Cretaceous). The monosporangiate [2] female Williamsonia seed cone (sometimes described as a "flower" though this does not imply homology with angiosperm flowers [3]) consists of an ovulate receptacle enclosed by bracts (modified leaves), with the receptacle bearing sporophylls with terminal seeds/ovules, which are surrounded by ...
It is a dioecious species, with male and female structures on separate plants. The male cone is brown with spiralling scales and measures 5 to 15 mm (0.20 to 0.59 in) long by 3 mm (1 ⁄ 8 in) wide. It grows from the leaf axils. The female cone has one scale bearing one seed about 1 to 2 cm (0.39 to 0.79 in) long.
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