278 MORPHOLOGY OP ANGIOSPERMS 



era, are practically all members of the Archichlamydeae. The 

 case of Viburnum, and even of Aralia, is peculiar, and perhaps 

 suggestive of a far more complete development of the Dicoty- 

 ledons than the records have shown. 



2. The early appearance of Populus confirms the general 

 primitive character of naked flowers and the anemophilous 

 habit. 



3. Xone of the known chalazogamic forms are represented 

 in the above list, so that chalazogamv can hardly be regarded 

 as a primitive character, as has been claimed, unless it be as- 

 sumed that these earlier genera were chalazogamic and later 

 became porogamic. 



4. Of the twelve modern genera represented in the list, no 

 less than eight are recognized by morphologists as primitive 

 in character. 



5. The occurrence of one of the Sympetalae in the upper- 

 most member of the Lower Cretaceous, and that an epigynous 

 form, needs explanation. It leads to at least one of three con- 

 clusions. Either the determination is a mistake, or a large 

 representation of sympetalous genera remain to be discovered 

 in the Lower Cretaceous, or the present view as to the relative 

 rank and phylogeny of sympetalous families must be modified. 

 If the determination of Viburnum is the correct one, its associa- 

 tion with Aralia is confirmatory of a genetic connection which 

 we have Ions - maintained. 



6. That epigyny had appeared among the undoubted Archi- 

 chlamvdeae during the Lower Cretaceous is seen bv the exist- 

 ence of such a genus as Eucalyptus. 



Upper Cretaceous Dicotyledons. — Much less is known 

 of the flora of the Tapper Cretaceous than of the Lower Creta- 

 ceous. There must have been a large development of existing 

 genera, such as Sali.r, Populus, and Liriodendron being well 

 known, as well as an introduction of new ones. 



Tertiary Dicotyledons. — The record of the dicotyledo- 

 nous flora of the Tertiary is naturally made up of the trees and 

 shrubs. The forest display was evidently as extensive and va- 

 ried as now. In addition to the genera mentioned above, all of 

 which show increasing development, there appeared the Betula- 

 ceae, Fagaeeae, Juglandaceae, Moraceae, Proteaceae, Berberi- 

 daceae, Staphyleaceae, Aceraceae, etc. This means an almost 



