EFFECTS OF EXTRAORDINARY SEASONS, ETC. 671 
south and perhaps to the north by Eocene Tertiary beds, and the 
appearance of the country indicates that a smaller lapse of time 
has separated the periods of their deposit than is usual. Never- 
theless no traces of Cretaceous types of vertebrates have yet been 
found in any of these Tertiaries. 
EFFECTS OF EXTRAORDINARY SEASONS ON THE 
DISTRIBUTION OF ANIMALS AND PLANTS. 
BY PROF. N. S. SHALER. 
WHATEVER throws any light upon the nature of the means 
whereby the changes in the character and distribution of organic 
forms have been effected, has for the student of geology the keen- 
est interest. I therefore venture to call attention to the peculiar 
effects of the last year upon the forests and probably upon some of 
the animals of New England. The year preceding the winter of 
1871-2 was one of the dryest on record in this region ; the rainfall 
was not only much less than usual, but came in such a fashion 
as to leave the ground very dry when winter came. The snowfall 
during the winter was slight and did not lie well upon the ground, 
melting and drifting in such fashion as to leave a large part of the 
surface quite unprotected. In this state the long continued and 
steady cold froze the earth to a great depth, and at some points the 
frozen ground was found as far as five feet from the surface. 
Over the whole of New England it was doubtless deep enough to 
involve the whole of the roots of the vegetation of our forests. 
It is doubtful whether it was the intensity of the cold alone which 
produced the effects which have been observed all about us, but 
more likely that it was in large part due to the deficiency of sap 
in the plants, in connection with the low temperature ; as the frost 
left the roots, they remained for some time in contact with rela- 
tively dry earth, thus causing a shock too great for their vitality 
to withstand. I do not see clearly just how the cold and drought 
cooperated in bringing about this destruction, though I have no 
doubt they worked together. 
The tree which suffered most is the arbor-vite ( Thuja occident- 
alis) for more than half of these are dead and a large part of those 
