THE WALNUTS AND HICKORIES 



77 



when Libya was separated from Europe and Asia by a vast Mediter- 

 ranean sea the Fayum was a delta with a heavy rainfall, clothed 

 with forests of an Indo-Malayan type, and inhabited by ancestral 

 elephants and other curious forms of ancient animal life. No less 

 than 8 kinds of figs, as well as laurels and camphor trees have 

 been described from this now arid and desiccated region, and among 

 these a species of walnut furnishes a striking commentary on the 

 changes which time has wrought in this region. 



Fig. 15. Winged Fruit of Engelhardtl4 from the Lower Eocene of 

 Mississippi 



I have attempted to give a graphic summary of our knowledge 

 of the present and past distribution of the walnuts in the accom- 

 panying sketch map (fig. 13) where the areas of distribution of the 

 existing forms (somewhat exaggerated) are shown in solid black. 

 It is possible that the part of the range of Juglans regia in southern 

 Asia should be extended eastward over Tibet through northern 

 China to Japan. All of the known fossil occurrences of walnuts 

 have been plotted and are enclosed within the vertically lined 

 area. Probably the southern boundary of this area should be 

 extended, far enough at least to include the present homes of the 



