Vegetative Characters, Growth Habit and Microsporangiate Strobilus of Lycopsid Minostrobus chaohuensis
Fig 4
Sections of the permineralized microsporangiate strobilus of Minostrobus chaohuensis in Fig. 3F, under LM.
(A) Longitudinal section of strobilus, showing sporophylls and sporangia. Arrow indicating portion enlarged in Fig. 4B. PKUB12189-3-4. Scale bar = 2 mm. (B) Enlargement of Fig. 4A (arrow), showing microsporangium with numerous microspores and alations (Al) of sporophyll. PKUB12189-3-4. Scale bar = 0.5 mm. (C) Radial section of strobilus, showing strobilar axis, sporophylls and microsporangia. Arrows indicating portions enlarged in Fig. 4D and Fig. 4J. PKUB12189-3-3. Scale bar = 2 mm. (D) Enlargement of Fig. 4C (upper arrow), showing sporangium containing microspores and subarchesporial pad. Rectangle indicating portion enlarged in Fig. 4I. PKUB12189-3-3. Scale bar = 0.2 mm. (E) Transverse section of strobilus, showing strobilar axis and microsporangia. Arrow indicating portion enlarged in Fig. 4F. PKUB12189-2-3. Scale bar = 1 mm. (F) Enlargement of Fig. 4E (arrow), showing exarch primary xylem of strobilar axis. PKUB12189-2-3. Scale bar = 0.1 mm. (G) Transverse section of strobilus. Arrows indicating transverse view of sporophylls. PKUB12189-1-4. Scale bar = 1 mm. (H) Transverse section of uniseriate sporangial wall, showing columnar cells and microspores in the sporangium. Rectangle indicating portion enlarged in Fig. 4K. PKUB12189-2-5. Scale bar = 0.1 mm. (I) Enlargement of Fig. 4D (rectangle), showing subarchesporial pad and microspores in sporangium. PKUB12189-3-3. Scale bar = 50 μm. (J) Enlargement of Fig. 4C (lower arrow), showing xylem strand of strobilar axis and metaxylem tracheids with scalariform thickenings. PKUB12189-3-3. Scale bar = 0.1 mm. (K) Enlargement of Fig. 4H (rectangle), showing microspore tetrads and the inner body. PKUB12189-2-5. Scale bar = 50 μm.