GENERAL RESULTS— PTEROPSIDA 659 



classical investigations, is essentially the same as in a 

 typical Angiospermous flower, with a central pistil, a 

 surrounding whorl of stamens, and an enveloping 

 perianth (see pp. 584, 585). The whole organisation, as 

 Dr. Wieland at once recognised, is best compared with 

 that' of the flower in Magnoliaceae, such as the Tulip- 

 tree (Liriodendrori), while the resemblance extends to 

 other orders of polypetalous Dicotyledons, e.g. Ranun- 

 culaceae and Nymphaeaceae. These groups, especially 

 the Magnoliaceae, have been widely accepted as rela- 

 tively primitive, and there is evidence for their occur- 

 rence in Cretaceous rocks. 



As we have seen, the gynaecium of Bennettiteae 

 shows some approach to the structure of a closed 

 Angiospermous ovary, while the seed was practically 

 exalbuminous, the large Dicotyledonous embryo filling 

 the embryo-sac — a condition otherwise met with only 

 among the Angiosperms. 



Taking the whole of the characters into consideration, 

 the evidence of affinity between the Mesozoic Cycado- 

 phyta and the Angiosperms appears very strong. It 

 cannot, of course, be supposed that the Bennettiteae 

 were on the direct line of Angiospermous descent, for 

 there are manifest points of difference, notably in the 

 great complexity of the stamens and in the organisation 

 of the ovary-wall or pericarp, which was not formed by the 

 carpels themselves, but by the associated sterile scales. 

 There may be a difference of opinion as to the near- 

 ness of the relation between Bennettiteae and the 

 higher Flowering Plants, but the points of agreement 

 are so striking that we can hardly fail to recognise 

 that a real relation exists, and that the ancestry of the 



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