pinnule


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Related to pinnule: pinnation

pinnule

a subdivision of a leaf pinna, often bearing SPORANGIA in ferns.
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2 and 5D): single, ribbed ovule organically connected to an ultimate rachis without replacing a pinnule of Neuropteris flexuosa Sternberg.
This concerns stems which kept their cylindrical volume as well as compound leaves showing pinnules lying in different planes however no anatomical detail is preserved.
13) climbed by leaflet tendrils, developed from specialized apical portions of pinnae, in which one or several of the pinnules are variously modified into tendrils (Fig.
What is still poorly understood is the position of the many illustrated laciniate pinnule forms within the frond structure of M.
Quantitative studies of pinnule development in the ferns Adiantum raddianum and Cheilanthes viridis.
Fertile pinnules of Danaeites rigida Gu & Zhi (Marattiales) from the Upper Permian of south China.
Rachis flat, 0.5-0.6 mm wide, rounded basally bearing subopposite pinnules 6-7 mm long and 2.5-3 mm wide, thin, subtriangular, slightly falcate and inclined forwards, with parallel, slightly dentate margins, rounded to obtuse apex, broadly based but not confluent, contracted basally.
However, the most striking characteristic of this morphospecies is its exceptionally large pinnules (> 2 cm long, locally [less than or equal to] 12 cm long), which show thick cuticle, sunken stomata and dense arrays of adaxial trichomes (Schabilion and Reihman 1985; Zodrow 2003).
e.j.gouda@uu.nl term correct application anterior applicable only in strongly zygomorphic flowers, but even there it remains doubtful posterior see anterior pinnate description of compound leaves with leaflets arranged on opposite sides of an elongated axis or of a certain venation pattern bipinnate twice pinnate (leaves), see above tripinnate pinnately compound three times, with pinnate pirmules (leaflets) quadripinnate pinnately compound four times, with nate pinnules (leaflets) scape leafless peduncle arising from ground level (usually from a basal rosette) in acaulescent plants (e.g.
In the course of evolution the fern sporangia shifted in position from terminal on rachis branches to marginal and finally superficial on the laminae of well-developed pinnules (Halle, 1935).
LEAF DESCRIPTION: BIPINNATELY COMPOUND, 18" to 36" overall length, 3 to 7 pairs of pinnae along the rachis, pinnae having 3 to 7 pairs of leaflets (pinnules), leaflets 1" to 2 1/2" long and half as wide, ovate shape with entire margins.