JET. 75.] TO A. DE CANDOLLE. 783 



What do I call an alpine plant ? Why, one that 

 has its habitat above the limit of trees mainly - 

 though it may run down lower along streams. But 

 in a dry region, where forest has no fair chance, we 

 might need to mend the definition. 



Upon your paper, I got a few notes offhand, by 

 references. 



I premise that in New England we have two places 

 where several alpine plants are stranded at lower 

 levels than they ought, peculiar conditions of configu- 

 ration and shelter having preserved them, while the 

 exposed higher grounds have lost them. They are 

 Willoughby Mountain and the Notch of Mt. Mans- 

 field, Vermont. 



As to your III. Of the whole list of alpine 

 plants of Oregon and northward and not of Cali- 

 fornia, I can put my hand upon only two that are yet 

 known in California, viz., Armania verna and Vac- 

 cinium caespitosum, which comes in its var. arbuscula 



only. 



There is a great lack of alpine arctic plants in Cali- 

 fornia. First, because there is not much place for 

 them now ; secondly, because there have been such 

 terrible and vast volcanic deposits lava and ashes 

 that they must have been all killed out. 



But for all these matters we shall one of these days 

 have fuller and surer data after my day. Well, I 

 must stop. . . . 



TO A. DE CANDOLLE. 



CAMBRIDGE, June 29, 1886. 



MY DEAR DE CANDOLLE, - Your letter and in- 

 closure of the 15th inst. gave me much pleasure. 

 Not only had I a natural curiosity to know more of 



