THE ANCESTRY OF THE BEECH 75 



and tectonic lines across Polynesia. It seems probable, how- 

 ever, that Australia and New Zealand were never actually 

 connected in later geologic times, that is to say, since the 

 higher plants were evolved. Otherwise New Zealand should 

 contain some traces of the animals such as the marsupials 

 and plants such as the eucalyptus that particularly char- 

 acterize Australia. New Zealand has, however, been shown to 

 have been much more extensive in former than it is at the 

 present time and it seems probable that it received its beeches 

 from the Antarctic continent rather than by a land bridge be- 

 tween New Zealand and Austraha. These suggested lines of 

 migration are seen to have been possible by referring to the 

 sketch map (fig. 2) which shows the approximate distribution of 

 land and water during the early Upper Cretaceous. 



If Fagus or even Nothofagus were of southei'n origin, and I 

 think that it will be conceded by botanists familiar with the two 

 genera that they are the immediate descendants of a common 

 stock, it would be contrary to the general rule of past distribu- 

 tion of the ancestors of our existing flora which in every case 

 that has been investigated show former cosmopolitanism in the 

 great land mass of the northern hemisphere and a simultaneous 

 or subsequent migration into southern lands. This statement is 

 notably true of the coniferous genera Araucaria and Dammara. 

 It is likewise true of the great antipodean families Proteaceae 

 and Myrtaceae, and many other and no less striking instances 

 could be enumerated. 



It would seem that Nothofagus was more primitive than 

 Fagus, or at least that it is more like the original stock from which 

 both took their origin. This stock was probably evergreen in 

 habit, small in size and with relatively reduced leaves. If this 

 supposition is justified it might be considered as furnishing an- 

 other argument for the northern origin and southward migra- 

 tion of the original stock, for the natural place to look for 

 existing forms most like their remote ancestors has been consid- 

 ered b}' some students of distribution as being farthest away 

 from the original center of radiation — nearer this center they 

 would tend to have been replaced by successively later and later 

 evolved forms. 



