184. BOTANICAL GAZETTE [SEPTEMBER 
of the records kept in Sackville in the marsh country, and must 
turn therefore to those of St. John. The above table, based on 
the averages fora long series of years, is supplied by the Dominion 
Meteorological Office at Ottawa. Owing to well-known local 
conditions, the summer temperatures average lower, and the winter 
higher at St. John than elsewhere in the province, and this cor- 
rection must be applied to the table to make it of use in estimat- 
ing the conditions of the marsh country. 
It is important to note further, that on the marshes them- 
selves the snowfall is said not to be great, and often for con- 
siderable periods in winter the ground is bare. This condition, 
combined with the strong winds that prevail there and the total 
lack of shelter on the marshes, makes the winter conditions 
unusually unfavorable for vegetation, which must consist of 
plants able to endure such trying conditions. For this no 
arrangement is better than that of the grasses, which largely 
retreat to or under the ground in winter. On the other hand, at 
times in summer, the marshes, lying at sea level and completely 
unshaded, receive so strong an insolation as to become very hot, 
though this is never long continued. 
Light—The latitude of these marshes is 45° 50’ to 46°, from 
which the amount of light they would receive if unshaded by 
clouds, etc., and with a clear atmosphere may be estimated. But 
the full amount is much diminished by cloudy weather. No 
records of cloudiness are kept nearer than St. John, where the 
percentages for a long series of years are as follows: 
Jan. | Feb. | Mar, 
| 
53 | 54} 60 
April} May | June} July | Aug. | Sept.| Oct. | Nov. 
Dec. | Year 
xl eel be 
63 | 62 | 53 | 58 | 60 | 59 | 58 
Probably the cloud percentage for the marshes is not very 
different from this, though it would be less rather than more, 
Say 50 per cent. for the year, 55-60 per cent. for the summer 
months. No records whatever for intensity of the light are 
available. It is important to note, however, that the marshes, 
perfectly level and unshaded, receive the full value of what light 
there is. 
