GEOGRAPHICAL DISTRIBUTION OF FOREST TREES IN CANADA. 289 



colonies of trees entirely separated from the main areas occupied by the 

 various species : 



1. Banksian Pine. One in Nova Scotia, and another in New 

 Brunswick. 



2. Wliite Pine. Several isolated patches near the northern limit of 

 this tree beyond the Upper Ottawa river, and others north of Lake 

 Superior. 



3. Red Pine. One on Big Black Island in Lake Winnipeg, dis- 

 covered by Mr. Tyrrell. Many of the groves on the head-waters of the 

 Abittibi river lie at some distance from one another, but all these are 

 included within the general northern limit. Sir John Eichardson 

 mentions an outlier of this species at Lac la Loche on the upper waters 

 of the Churchill river, but subsequent observation has shown it to be a 

 grove of Banksian pines. 



4. White Cedar. The outliers on the east side of the Bay of Fundy 

 and on the west end of Prince Edward Island have been already referred 

 to, as well as the remarkable one of Cedar Lake at the mouth of the 

 Saskatchewan. Along the general boundary of this tree isolated groves 

 occur in favourable situations, such as on limestone rocks and around 

 the shores of lakes, where the warm season is prolonged by the slow 

 escape of the heat which has been stored up in the water. 



5. Hemlock Spruce. A colony is said to exist near Thompson, in 

 Minnesota, a short distance west of the head of Lake Superior; but 

 the tree does not occur on the Kaministiquia river, Thunder Bay, as 

 supposed by Sir John Kichardson. 



6. Balsam Poplar. Several small patches occur on the headwaters 

 of the Bell river, within the great area from which it is otherwise absent. 



7. Basswood. There is an outlier of this tree at Lake St. John, north 

 of Quebec, and nearly one hundred miles beyond the general limit of the 

 species. 



8. Beech. A small colony of this species occurs about two miles 

 north of the town of Massey on Spanish river ; but it is only a few miles 

 outside of the main boundary. The beech does not occur on the Red 

 river of the North, as erroneously mentioned by Sir John Eichardson, 

 nor in the treeless region of Back's Great Fish river, as inaccurately stated 

 by Dr. Sutherland. 



9. Buttonwood. A number of these trees were growing a few years 

 ago along the Sageen river in the county of Bruce, far outside of the 

 main boundary. 



The occurrence of outliers of so many species tends to disprove the 

 theory that these phenomena are evidences of the dying out of a species 

 on account of the antiquity of its origin. They are rather to be re- 

 garded as the precursors of the advance of the boundaries of the several 

 species, the general tendency being towards enlargement. 



VACANT SPACES. 



Blanks, or spaces within the general area of distribution of any tree in 

 which no specimen of it can be found, are more liable to be overlooked 



