1905] TRANSEAU—BOGS OF THE HURON RIVER VALLEY 357 
of the “raised bog.” Certain temperature phenomena associated 
with the bog habitat will be discussed in connection with the analysis 
of the life conditions obtaining in bogs. : 
Rainjall—In the following table is given the mean monthly and 
annual precipitation for seven stations located within or near the 
Huron basin. As their individual variation is but small, it is probable 
that the average for the stations gives a fair estimate of the rainfall 
and its distribution. Appended are the corresponding records for 
the maritime region of eastern Canada: 
MEAN PRECIPITATION IN INCHES. 
Alt. 
: f ord 
vy 2 Jan. | Feb. | Mar.| Apr. | May | June | July | Aug. | Sept.| Oct. | Nov.| Dec. | Ann. 
Ts. 
ra 930] 23 | 1.99] 2.19] 2.12) 2.88] 3.72| 3.30] 2.82] 2.45] 2.58) 2.82) 2.77 2.35)32-08 
Jack +| 736} 18 | 1.97] 2.61| 2.48] 2.24| 3.08] 4.02| 3.09] 2.24] 2.63] 2.70] 3.20) 2-32)33- 
yc 927| 6 | 2.06) 2.21| 3.14| 1.26| 3.22| 3.02| 2.47| 1.76] 1.74] 3-61| 2.87 1. 56)28.02 
Ball Mt 924] 11 | 1.98] 2.10| 2.42| 2.60| 3.38] 2.44| 2.66] 2.85| 1-03] 2-04] 2.64 1.77|26.05 
Birm’gham 932) 13 | 1.73] 1.76| 2.07| 2.12| 3.52| 3.13| 2-47| 2-50| 2-62] 2.60] 2.71) 2-30/20-72 
venetian 860) 15 | 1.91] 2.00 2.32| 2.53] 3.36] 3-15| 2.56| 2.38] 2.33) 2-51| 3-9 1.88)20.95 
Average. 1.94} 2.16] 2.42| 2.27| 3.53| 3.10| 2.68| 2-38| 2.30| 2-73] 2-88) 2.03|30-22 
ee 
Haliin ? | 5.55| 3.03| 3-80| 2.50] 3.66] 2.72| 3.20| 4.64] 3-08] 4-13) 4-78] 5-1047-47 
N - 
S(sz) 22 | 5-63) 4.94) 5.15) 4.00] 4.43] 3.68] 3.43] 3-96) 3-53] 5-27 5.26] 5-52|57-74 
eet | ee Re es ee 
It will be noticed from the above data that the precipitation is 
duite evenly distributed throughout the year. It reaches its maximum 
during the months of May and June, when the vegetative processes 
of the bog plants are most active. It approaches its summer mini- 
mum during July and August, when the temperature commonly 
— its greatest height. The former implies that the water level 
a hg is kept at or above the surface of the substratum for weeks 
¥ Ome. The latter involves strong transpiration on the part of the 
Yegetation, when the water supply must be drawn for the most part 
the substratum. The average number of rainy days during the 
Past five years is one hundred per annum. 
‘ — average snowfall in this region during the five years, 1898 i 
eg “mounts to 38.4 inches (975 ™™). In the case of the bogs this 
ton aa is usually increased by the drifting of snow from the sur- 
the g hills. Observations during the past two winters show that 
are covered by ice to a thickness of a foot (30 om) 08 THORS. 
