A male flower of the Pentoxyleae with remarks on the structure of the female cones of the group

Vishnu-Mittre

doi:10.54991/jop.1953.435

Authors

Vishnu-Mittre Birbal Sahni Institute of Palaeobotany, 53 University Road, Lucknow 226007, India

DOI:

https://doi.org/10.54991/jop.1953.435

Abstract

Under the name of Sahnia nipaniensis gen. et sp. nov. the author describes some specimens which he believes to be the male flowers of the Pentoxyleae. These were borne apically on dwarf shoots closely resembling those of Pentoxylon Sahnii Srivastava. The flower consists of filiform spirally branched microsporophylls, fused proximally to form a disc which surrounds a broad and conical receptacle. The unilocular sporangia are borne at the ends of short branches of the sporophylls. Pollen grains are monocolpate and boat-shaped. In young flower the microsporophylls are surrounded by a whorl of deciduous bracts.

The infructescence of Carnoconites laxum and several specimens (showing longitudinal section) of the infructescence of C. compactum have also been discovered. The infructescence of C. laxum differs from that of C. compactum in having much shorter pedicels and much longer female cones. The infructescence of C. compactum differs from the reconstruction made by Professor Sahni in the absence of bifurcation of the pedicels and in the arrangement of the cones.

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References

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