By Pant, D.D. and Osborne, R. and Birbal Sahni Institute of Palaeobotany
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B> .... ~ ~ ; .. ' s ®J Fig. 9. Lyrasperma scotica. A, B, longisections of seed in minor (subsidiary) and major (principal) planes. C·J, successive transections of seed at levels indicated by c-i in B (all after Long. 1960c). a - archegonium. cc - central column. it integument lobe. la -lagenostome. mm - megaspore membrane. n - nucellus. pc - pollen chamber. pl- pollen. pr - female gametophyte. s - salpinx. se - sclerotesta. vb - vascular bundle. w - wing. which become hooked to the whip-like processes.
Caytoniales Class 2. Cycadopsida Order 7. Cycadales 41 3. CLASSIFICATION Class 3. Pentoxylopsida Order 8. Pentoxylales Class 4. Bennettitopsida (Cycadeoideopsida) Order 9. Bennettitales (Cycadeoideales) Division 2 - Chlamydospermophyta Peculiar angiosperm-like forms. Class 1. Gnetopsida Order 1. Gnetales Order 2. , Harrisiothecium marsiliodes (Hams, 1935), Buriadia heterophylla (Pant & Nautiyal, 1967), which may require separate orders for themselves, are not assigned any position in the above scheme.
P. c\tV Bo Q Q. ' ~ b. : aJ 00 F Fig. 3. Genomosperma kidstonii. A, seed in median longisection. B-J, successive transections of seed at levels indicated by b-j in A. (all after Long, 1960a). furnished by Xenotheca devonica, Hydrasperma tenuis from Ireland and Archaeosperma amoldii (Fig. 1F). Similar more evolved Carboniferous seeds include Genomospe rma latens (Long, 1961) w here the integumentary lobes are fused up to two thirds of their length from the base and free above (Fig. 5B-E). At the distal end of the seed the integumentary processes coalesce to form a rudimentary composite micropyle.