Wee fe a ————— 
1903 | VEGETATION OF THE BAY OF FUNDY MARSHES 185 
Air.— Here as elsewhere, chemically the air is hardly an 
ecological factor; at all events it is not a differential factor. 
Atmospheric pressure on the marshes, lying at sea level, is of 
course at its maximum, but the daily fluctuations of the barome- 
ter, as Schimper remarks, have no known effects upon the form 
or distribution of vegetation. Mechanically, however, as it 
moves in winds, the atmosphere is here important. Unfortu- 
nately no official meteorological records are available for direc- 
tion or velocity, but a record of another kind is visible and 
unmistakable, namely, the wind effects upon the vegetation. 
As I have elsewhere pointed out,” the trees and shrubs on the 
neighboring ridges and in places on the margins of the bogs are 
strongly bent to the northeast, and show a great development of 
branches on that side, with an abortion on the southwest. This 
is caused by the very strong southwest winds which prevail 
here, as the residents agree, during most of the year, a phe- 
nomenon resulting from the position of the marshes in relation 
to the Bay of Fundy. This great bay lies northeast and south- 
west, and is of the form of a huge funnel. Wide at its mouth, 
it narrows between walls of increasing height (300 to 700 feet or 
more) towards its head. At Cape Chignecto the northern 
branch, with which we are concerned, continues and even intensi- 
fies this funnel character, ending finally in the low-lying marsh 
country. The great winds here are due to very much the same 
Causes as the great tides. Every wind froma southerly direction 
is thus brought into a southwesterly course, condensed, strength- 
ened, and poured over the low-lying marsh country, and the 
vegetation must be of a kind to endure it, for which nothing is 
better than the grasses. 
It might be expected, as a result of the prevalence of these 
winds, that dunes would be formed on the unreclaimed marshes. 
There is, however, not the least trace of this, chiefly because the 
mud when laid down by the tide hardens as it dries, allowing the 
wind no hold upon it. 
The constancy and strength of the winds on the marshes 
Must greatly promote evaporation (transpiration) from any 
* Bull. Nat. Hist. Soc. New Bruns. i: 24. 
