ROCKY MOUNTAIN MEDICAL ASSOCIATION. 1 5 
At our last meeting I was chosen your President, 
an honor which imposed the duty to address you on 
this occasion. 
The selection of a subject worthy of your attention 
has caused me solicitude: and in the choice of a 
theme, 1 found myself almost involuntarily led to con- 
sider some of the problems discussed with my com- 
panions when crossing the great American plains. 
While we traveled for days through an uninhabited 
country, the mind was almost compelled to a retro- 
spection, and to ponder over the existence of these 
immense interior plateaus and the fact of their being 
nearly destitute of population, of timber, and in a great 
degree of birds and animals. Was it always so ? 
Were these vast regions always so poorly supplied 
with animal life? I think not. The testimony of the 
scientists who have examined the country is that ample 
evidence exists that at some remote period it had a 
numerous flora and fauna, which no longer exists 
and which possibly included man. With the aid of 
the imagination and with the light of recent discov- 
eries, the attempt in fancy to review the great dead 
past, and by these means to repeople North America 
with its long-departed inhabitants, was on that occa- 
sion a most agreeable pastime. 
I am aware that a scientific discussion of the subject 
would require me to treat of the animals and plants in 
the order of their appearance, to be deduced from geo- 
logical evidences. As plants preceded animals, so ani- 
Sayer, D. M., died August 3, 1876, aet. 69. 
Thomas, William, died April 2, 1875, set. 70. 
Average age of deceased, 58 years. 
