61:2.4

Marked changes were taking place in the fauna of the planet. The sea life was undergoing great modification; most of the present-day orders of marine life were in existence, and foraminifers continued to play an important role. The insect life was much like that of the previous era. The Florissant fossil beds of Colorado belong to the later years of these far-distant times. Most of the living insect families go back to this period, but many then in existence are now extinct, though their fossils remain.