216 DARWINIANA. 



Moreover, the Torreya of Florida is associated with 

 a yew ; and the trees of this grove are the only yew- 

 trees of Eastern North America ; for the yew of our 

 Northern woods is a decumbent shrub. A yew-tree, 

 perhaps the same, is found with Taxodium in the 

 temperate parts of Mexico. The only other yews in 

 America grow with the redwoods and the other Tor- 

 reya in California, and extend northward into Ore- 

 gon. Yews are also associated with Torreya in Japan ; 

 and they extend westward through Mantchooria and 

 the Himalayas to Western Europe, and even to the 

 Azores Islands, where occurs the common yew of the 

 Old World. 



So we have three groups of coniferous trees which 

 agree in this peculiar geographical distribution, with, 

 however, a notable extension of range in the case of 

 the yew : 1. The redwoods, and their relatives, Tax- 

 odium and Glyptostrobus, which differ so as to consti- 

 tute a genus for each of the three regions ; 2. The Tor- 

 reyas, more nearly akin, merely a different species in 

 each region ; 3. The yews, still more closely related 

 while more widely disseminated, of which it is yet 

 uncertain whether they constitute seven, five, three, or 

 only one species. Opinions differ, and can hardly be 

 brought to any decisive test. However it be deter- 

 mined, it may still be said that the extreme differences 

 among the yews do not surpass those of the recognized 

 variations of the European yew, the cultivated races 

 included. 



It appears to me that these several instances all 

 raise the very same question, only with different de 



