316 PHYLUIvI XIV. AXTHOPHYTA 



the flints: while still another (the Cup Flowers) begins 

 with the Strawberries and culminates in the Sunflowers 

 and Dandelions. It will be noted furthermore that the 

 Axis Flowers and Cup Flowers agree in regard to their 

 cotyledons, arrangement of leaves, vascular bundles of 

 stems and leaves, and perianth whorls, causing us to 

 consider them as two subdivisions of a common class, — 

 Dicotyledons, — coordinate with the Monocotyledons. 



579. Taking a longer look backward it may be seen 

 that in the Anthophyta we have the culmination of the 

 evolutionary tendencies manifested in the main line of 

 plant progress over which we have travelled: — from 

 Myxophyceae to Chlorophyceae, thence to the lower 

 Bryophyta, and from these to the Old-fashioned Ferns 

 (Pteridophyta) and from these again to the Seed Ferns 

 and Flowering Plant Ancestors (in Cycadophyta), from 

 which the step is relatively short to the simpler Flowering 

 Plants. It follows that but five of the preceding phyla 

 have contributed to the development of the Flowering 

 Plants, and that the eight remaining phyla are side 

 branches whose developmental accretions added nothing 

 that continued to the Flowering Plants. These five 

 contributing phyla contain somewhat less than one-fourth 

 of the non-flowering plants, and yet it may be doubted 

 whether even more than one-fifth of these again con- 

 tributed in any way to the structure of the Flowering 

 Plants. So we may say that of the approximately 

 100,000 plants in the thirteen phyla preceding Antho- 

 phyta, probably no more than 5,000 represent structures 

 in any sense ancestral. 



580. It will be instructive to enumerate the greater 

 steps in this progressive development from the Myxo- 

 phyceae to Anthophyta, as follows: 



