THE MAPLE 223 



The leaves and fruits of extinct kinds of maples are less abundant 

 in the succeeding deposits of Pliocene age than they are in Miocene 

 deposits, but they were still a prominent element in the forests 

 of that time, about forty different species having been already 

 determined. Twelve of these, all Mediterranean forms in Spain, 

 France, Germany, Austria, Styria, Slavonia and Asia Minor, were 

 survivors from the Miocene. Pliocene maples are most abundant 

 and varied in France, where 12 different species have been found. 

 Italy ranks second with 10 species. No Pliocene maples have been 

 discovered in North America, although maples were undoubtedly 

 present in both the eastern and western parts of the continent at 

 that time. In Asia Pliocene maples have been found in Indo-China, 

 Manchuria Japan, and in the Altai region of the central part of 

 that continent. These are mostly forms of Japanese and Chinese 

 affinities, where the descendants of these late Tertiary species now 

 live, and several of the fossil forms are undoubtedly the direct 

 ancestors of the latter. 



A quite considerable variety of maples have been found in the 

 Pleistocene deposits of North America and Europe, and as might 

 be expected, most of these are forms which still exist in modern 

 times. The stately sycamore maple of Europe, Acer pseudopla- 

 tamis, was already present in Phocene times in France and in the 

 Pleistocene it has been found in France, Italy, Luxembourg and 

 Hungary. The existing Acer campestre is found in the Pleistocene 

 of Germany, France, and Italy. There is a third form in Germany 

 and 2 additional in Italy. 



The records of Pleistocene maples in North America extend from 

 Ontario and Massachusetts to Alabama and Florida. The sugar 

 or rock maple, Acer saccharum, is found fossil in southern Ontario 

 and New England: the silver or white maple, Acer saccharinum, 

 has been found in Alabama: and the red or swamp maple, Acer 

 ruhrum, occurs in the Pleistocene of Alabama and Florida. There 

 are still other, not exactly named fossil maples in Virginia and Mary- 

 land, and a supposed extinct species has been described from the 

 interglacial deposits of the Don valley near Toronto, Canada. 



