A caution in regard to instinct--A useful law--Senses of
fishes--The mind of a minnow--The mind and senses of
amphibians--The reptilian mind--Mind in
birds--Intelligence co-operating with instinct--The
mind of the mammal--Instinctive aptitudes--Power of
association--Why is there not more intelligence?--The
mind of monkeys--Activity for activity's
sake--Imitation--The mind of man--Body and mind.