MICHIGAN ACADEMY OF SCIENCE. 145 



activity. procUiction of secondary bundles, etc. This viewpoint 

 probably arose from tlie fact that most of the active botanists of 

 the world have reside<l in the North Temperate zone wliere the ma- 

 jority of species and the prevalent families are herbaceous. Another 

 possible reason for this viewpoint lies in the teaching of dicotyle- 

 donous stem-structure from forms with separate vascular bundles, 

 it beinjj tauoht directly or by inference that this is the tyi)ical 

 dicotyledonous structure and that the woody cylinder is derived 

 froui it. I plead guilty to haviug both taught and written to this 

 effect even in recent years: A third reason for this view is ])erhaps 

 the fact that the forms of ferns and lycopods with which the 

 botanist of the North Temperate zone is mostly familiar are herba- 

 ceous, so that in considering these as in the ancestral line of the 

 Anthophyta, he is naturally inclined to look for herbaceous forms 

 in the flowering plants, too, as being the more typical. 



More recently, however, it has begun to be pointed out that the 

 line of development within the Dicotyledoneae must have been, not 

 along a series of herbaceous families, but rather along a line of 

 woody families Avith numerous short side-lines of herbaceous plants 

 as offshoots from the main line. Thus for examjde Eames, in 

 1911" pointed out that the primitive Angiosperms were more prob- 

 ably woody, with a continuous woody cylinder. That this structure 

 is primitive is shown by the fact that it still occurs in the seedlings 

 of many herbaceous plants. In 1913 various considerations led C. 

 E. Bessey and the writer to this same conclusion which v^nas ex- 

 pres.sed by the former^^ in the assignment of the first (i. e. most primi- 

 tive) place among the Dicotyledoneae to the MagTioliaceae instead 

 of to the Ranunculaceae as was done in his earlier writings. Re- 

 cently Sinnott and Bailey^*"' have been devoting much thought and 

 research to this question of the phytogeny of the Angiosperms and 

 have pointed out that whereas in the Temperate zone the herbaceous 

 plants make up from 54 to 93 per cent (depending upon the region) 

 of the species of flowering plants, they make up only for 12 to 54 per 

 cent of the species in the Tropics, and this in spite of the large 

 number of Monocotyledons which (excepting Palms and a very few 

 other families) are all herbaceous. 



Viewed in this light we would now consider the primitive An- 

 thophyta to have been trees, dicotyledonous in stem and seedling 

 structure, with large apocarpous flowers; with as their nearest 



14. Eamcs, A. J. On the Origin of the Herbaceous Type in the Angiosperms. 1911. 



15. Bessey, C. E. Revisions of Some Plant Phyla, p. 41. 1914. 



16. Sinnott. Edward W. and Bailey. Irving W. Investigations on the Phylogeny 

 of the Angiosperms : Xo. 4. The Origin and Dispersal of Herbaceous Angiosperms. 

 1914. 



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