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nature jacketed it with underwear of down and outer
garments of feathers, and the greater the danger of
heat reaction the greater the thickness and extent of
this jacketing. Since feathers were not necesary
to flight it is not probable that birds were clothed
with feathers until this extra energy began to show.
[it] seff. Nature being [...] to make the
time became lavish in her gift.

Scales were not suited for heat conservation
in fast they increased heat induction.

A cold blooded animal is one that has the
temperatire of its surroundings and it necesarily
[must] become [imured], with out shock, to a
constantly cold, watery environment. Its body heat
produced by internal [...] would thus be [lift]
low by the conduction of that heat through the scales
and no shock would be experienced from a medium of
low temperature.

Birds were destined to inhabit a regine of
[divversiued] temperatures. Those best clothed could
migrate over the greatest range of climate in
search of food. For this purpose feathers are admirable
[reiment]; drawn close they allow greater radiation and
cooling fluffed out; they increase the depth of dead air
space about the bird and conserve more heat.
Fishes and reptiles have pres in the skin from
which secretions [pove] for various purposed. Rapid