114 OKIGIN OF LIFE IN AMEEICA 



In a later chapter I shall mention many of these. I would 

 only here draw attention to a striking botanical example 

 which seems to me due to direct migration from Europe to 

 western North America and not by way of Bering Strait. 



Anemones are so much cultivated now in gardens that 

 almost everyone is familiar with them. Their geological 

 history no doubt has been a very remarkable one. Not a 

 single fossil anemone is known to science, because the plant 

 contains no part that might readily be preserved, and yet it 

 can be asserted that the genus must have originated in very 

 remote times. The occurrence of many species in isolated 

 mountain regions, the extremely discontinuous and wide 

 range of others, and especially the high percentage pf 

 endemism, clearly imply that we have to deal with an ancient 

 genus. Dr. Ulbrich,* to whom we are indebted for a splendid 

 monograph of the genus Anemone, is of opinion that some 

 of its sections were already developed in early Tertiary times. 

 His view is, of course, entirely derived from what we might 

 call circumstantial evidence, just as Dr. Stejneger's was in 

 regard to the age of the genus Cinclus. One of these species 

 of anemone (A. baldensis), a well-known alpine plant, is, 

 according to Dr. Ulbrich, probably of Miocene age. It grows 

 also in the Carpathians, the Apennines, the Pyrenees and 

 northern Spanish Mountains, but nowhere in Asia. Never- 

 theless, the same species occurs in the highest elevations of 

 the Sierra Nevada in California, in the Cascade and Rocky 

 Mountains. A very closely-allied form of anemone (A. teto- 

 nensis) lives at a height of over 10,000 feet in Idaho, and 

 another (A. jamesoni) at about the same elevation in the 

 Andes of Ecuador. All these nearly related forms, there- 

 fore, are confined to Europe and western America. 



Among all the older American forms both of animals 

 and plants, other possible routes of migration besides the 

 Bering Strait one have to be taken into consideration. Re- 

 turning to the birds again, it seems to me that the genus 

 Regulus to which the European golden-crested wren belongs, 

 must have entered North America in Pliocene times along 

 with the great mammals alluded to in the last chapter. In 



* Ulbrich, E., " Q-eograph. Verbreitung d. Gattung Anemone," p. 325. 



