TIME AND CHANGE 
the amphibians in July or August, the reptiles in 
August or September, the mammals in October or 
November, and man in December, — separated 
from the first beginnings of life by all those mil- 
lions upon millions of years. 
Tf life is a ferment, as we are told it is, how long 
it took this yeast to leaven the whole loaf! Man 
is evidently the end of the series, he is the top of 
the biological tree. His specialization upon physical 
lines seems to have ended far back in geologic time; 
his future specialization and development is evi- 
dently to be upon mental and spiritual lines. Na- 
ture, as I have said, began to tend more and more to 
brains in the early Tertiary, — the autumn of the 
great year; her best harvest began to mature then, 
her grain began to ripen. Indeed, this increased 
cephalization of animal life in the fall of the great 
year does suggest a kind of ripening process, the 
turning of the sap and milk, which had been so 
abundant and so riotous in the earlier period, into 
fibre and fruit and seed. 
May it not be that that long and sultry spring and 
summer of the earth’s early history, a time prob- 
ably longer than has since elapsed, played a part 
in the development of life analogous to that played 
by our spring and summer, making it opulent, varied, 
gigantic, and making possible the condensation 
and refinement that came with man in the recent 
period? 
22 
