1866.] 



DAWSON — ON POST-PLIOCENE PLANTS. 



71 



bogs in Canada, Nova Scotia and Newfoundland, and thence, 

 according to Hooker, to the Arctic circle. It is also European. 



2. Acer spicatum Lamx. (Acer montanum Aiton.) Leaf 

 in a nodule from Green's Creek. Found in Nova Scotia and 

 Canada, also at Lake Winnepeg, according to Richardson. 



3. Potentilla Canadensis Linn. In nodules from Green's 

 Creek ; leaves only preserved. I have had some difficulty in 

 determining these, but believe they must be referred to the species 

 above named or to P. simplex Michx., supposed by Hooker and 

 Gray to be a variety. It occurs in Canada and New England, 

 but I have no information as to its range northward. 



Fig. 1. Gaylussaccia resinosa. 



4. Gaijlassaccia resinosa Torrey and Gray. Leaf in nodule 

 at Green's Creek. Abundant in New England and in Canada, 

 also on Like Huron and the Saskatchewan, according to Richardson. 



Figs. 2 and 3. Populus balsamifera. 



