CHAPIER V 
THE CONQUEST OF THE DRY 
LAND 
Tell-tale Evidences of Marine Ancestry—Origin of Land 
Plants—The Three Great Invasions of the Dry Land— 
New Ways of Breathing—Changes in Movements—New 
Ways of Looking after the Young—New Kinds of Pro- 
tection — Betwixt-and-Between Animals— Haunts within 
Haunts—Beneath the Ground—Cave Animals—Arboreal 
Life. 
VER and over again in the history of 
animal life some adventurous members 
of aquatic races have become colonists of the 
dry land. Perhaps we should not be quite 
wrong if we said, a little fancifully, that one 
of the great unspoken wishes of animals was 
to get out of the water. In any case, it is 
almost certain that the great majority of the 
different classes of land animals had their an- 
cestry in the sea, some of them making the 
transition—which might require millions of 
years—through fresh waters. 
We must be careful here to see the facts 
clearly. Land mammals had their origin in 
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