12 



A NATURALIST IN WESTERN CHINA 



Dr. Asa Gray when investigating the early collections made in 

 Japan. Modern work in China, and especially central China, 

 has given overwhelming evidence and established beyond 

 question Asa Gray's conclusions. There are many instances 

 in which only two species of a genus are known — one in the 

 eastern United States and the other in China. Noteworthy 

 examples are the Tulip tree, Kentucky Coffee tree, the Sassafras, 

 and the Lotus Lily [Nehimbium). A considerable number of 

 families are common to both countries, and in most instances 

 China is the dominant partner. Usually the U.S.A. have one 

 and China several species of the same genus, but here and 

 there the opposite obtains. Magnolias afford a good illustra- 

 tion of this affinity. This genus, absent from Europe and 

 western North America, is represented by 7 species on the 

 Atlantic side of the North American continent, and by 19 

 species in China and Japan. 



The following brief Hst still further illustrates this : — 



SOME GENERA COMMON TO CHINA, JAPAN, AND THE ATLANTIC 

 SIDE OF THE UNITED STATES OF AMERICA 



In a few cases the same species is common to both countries. 

 The most extraordinary instance of this is Diphylleia cymosa 

 (Umbrella Leaf). This plant occurs in localities separated by 

 140° of longitude and exhibits absolutely no marked variation. 



In the instances mentioned above, the families are absent 



