260 
At Mud Lake, north of Ann Arbor, where Chamaedaphne 
occurs in the openings in the spruce and tamarack, the snow was 
regularly deeper, a general level being 80 to 90 cm. (31—36 inches) 
and up to 110 cm. (43 inches). In wind-sweeps the snow level 
during the very cold weather was about 50 cm. 
In order to express the results other than through general 
impression by eye, in May, 1912, the per cent of dead flower 
buds out of the total number of buds produced in the spring of 
Fic. 3. Twigs of Chamaedaphne, in the upper the outer end killed. (From 
material collected at Mud Lake, May 9, 1912.) 
I9II was ascertained for different levels above the ground. 
Strips 20 cm. wide running from the outside of the bush to the 
center were selected and the total number of blossoms and dead 
buds were counted in IO cm. intervals from the ground to the 
top of the bush and the results tabulated. 
In every case where bushes had been entirely covered with 
snow, the per cent of blossoms was 98-100 per cent of possibility. 
Where the bush was only partly covered, at the snow level, 
there was an abrupt change in the per cent of blossoms from 
about 80 per cent and higher to less than 30 per cent and to zero 
in the tops of the higher bushes. When flowering occurred at all 
