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Cladostrobus Zalessky, 1918, is a male strobilus with spirally arranged microsporophylls, having a rhomboid lamina and a long stalk. The sporangia occur in groups. Microspores are of monosaccate type and are without a haptotypic mark. The name Cladaitina dibnerae gen. et sp. nov. is introduced for isolated spores of this kind. Cladostrobus may be a male strobilus of plants that bore Rufloria leaves. The group Cordaitales, as known now, comprises a heterogeneous assemblage of incompletely known plants, mostly sterile leaves. An artificial classification is proposed for sterile leaves, similar to the one already in vogue for dispersed spores and pollen. This classification is in fact a key for identification and cataloguing, and is not meant to show natural affinities.

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Gamoheterotopy (the transfer of characters from one sex to another) is very common in animals, and it is quite possible that it also played an important role in the evolution of plant fructifications. The gamoheterotopic origin of the angiosperm gynoecium by a transfer of the bennettitalean microsporophyll structure to the seed‐bearing organ is suggested. A bennettitalean ancestry of angiosperms agrees well with other characters (wood, pollen and stomatal structure, etc.) as well as circumstantial evidence.

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