SE eee ee ee 
FOREST VEGETATION. 23 
proper limits by climatic iufltences, but that’ the sae inthe 
of the atmosphere by the salts of the ‘eer aE e in the 
division of the forest i soaiproate What that share is, or what 
influence the climatic effects exert, is de nd the obj ney ae this 
communication ; but they may be incidentally refered to, where 
2 comparison between the occurrences on the plateau and those 
in its vicinity may tend to eliminate any point in the inquiry. 
The greater portion cf Central New England is composed of 
granitic formations. These occupy very large tracts, and in the 
which in wet weather it is almost impossible to travel. The 
granite for the most part is similar to specimens rg Q, and 
the soil formed from its detritus retains a ve rge amount of 
oisture ; so that if the wheels of a vehicle breale thiongh the 
outer crust, the aig eins matter from below spirts up “and is 
of which it is ceaauk impossible to be 
exteaitod’ N arapseath sehets of such country as this eat about 
G 
Severn and Mole Sasi is composed almost a ee of such 
the more rugged tracts, ie Pep. rmint becomes more and more 
the proslinaiaiart timber ; and i i 
than in other growths on tuiide Se: On the banks of the streams 
in such localities the sally occurs, and occasionally enters into 
combination with the peppermint somiut for some ea distance back. 
pn = mall-leafed shrubby tea-tree, Lept ifoliwin 
in the bed of the eta but is te found beyon d 
the limits of of the bank. In t tracts in which the granite 
, Vario 
contains a a oe DE rapht of Aamir than that deseri 
g ‘sig 
ee the genus- 
