The mammalia include not only man, the head of creation, but, generally,
those animals which have the most numerous and perfect faculties, the
most delicate perceptions, the most varied powers, and the highest
degrees of intelligence. All the species have a double heart; red, warm
blood; and a nervous system more fully developed than that of any other
animals. This class is divided into nine orders, under each of which we
shall notice some of the more remarkable species.