REMARKS UPON THE DISTRIBUTION OF ANIMALS AND PLANTS. S73 



Trientalis Americana. 



Rhinanthus Crista-galli. 



Melampyrum Americanum. 



Rumex Acetosella. 



Betula papyracea ; var. minor. 



Alnus viridis. 



Abies balsamea ; var. nana. 



Veratrum viride. 



Clintonia borealis. 



Streptopus roseus. 



S. amplexifolius. 



Listera cordata. 



Habenaria dilatata. 



H. obtusata. 



Luzula parviflora ; var. melanocarpa. 



Juncus filiformis. 



Eriophorum vaginatum. 



Carex canescens ; var. vitilis. 



C. rostra ta. 



C. arctata. 



C. trisperma. 



C. limosa. 



C. irrigua. 



Phleum pratense. 



Agrostis scabra. 



A. canina. 



Aira flexuosa. 



Avena striata. 



Trisetum subspicata ; var. molle. 



Aspidium spinulosum. 



REMARKS. A careful comparison of the names of plants assigned to the two alpine 

 districts in the lists above with those in the catalogue (Chapter XIII), shows that they 

 do not harmonize perfectly. Different observers, without an opportunity for comparing 

 notes and specimens, cannot be expected to agree in every minute particular ; and Dr. 

 Barrows and Mr. Flint have had no opportunity for interchanging their views. Each 

 one mentions two or three species not given by the other. They do not enter upon 

 the question of separating the alpine from the sub-alpine species. I commenced an 

 investigation, hoping to be able to find distinctions in the distribution of these plants 

 which might correspond with those among the insects mentioned by Mr. Scudder (p. 

 336), but have been doomed to disappointment. Prof. Gray's opinions, as held in 

 1856, are indicated, but these do not agree with those proposed by other eminent 

 botanists with whom I have been in correspondence. These two districts are so near 

 each other, and so limited in extent, that the climatic conditions are very nearly the 

 same. Hence the species may have emigrated from their original limits, both upwards 

 and downwards, so that the boundary line cannot be drawn. Another cause of inter- 

 mingling may have been the climatic fluctuation intimated by the former occupation 

 of the Canadian region by the Alleghanian forms up to the base of the mountains 



(P- 543). 



As the evidence from the plants themselves is obscure, I think we may be warranted, 

 in the further study of this subject, to assume as correct the insectean bounds given on 

 Plate C, Chapter XII. Then notes should be taken of the distribution of all the plants 

 above the line of trees. Should the facts thus gained not arrange themselves satis- 

 factorily, the only other course is to study the distribution of the same species about 

 Hudson's bay, Greenland, and other alpine districts, ascertain the denizens of the two 

 zones in typical localities, and then assign to each group those of the White Mountain 

 plants that are represented farther north. When we find fifty-eight species of Cana- 



