Mammalia in the 10th edition of Systema Naturae

In the 10th edition of Systema Naturae (published 1758–1759), Carl Linnaeus described the Mammalia as one of the six classes of animals, characterized by being:

Animals that suckle their young by means of lactiferous teats. In external and internal structure they resemble man: most of them are quadrupeds; and with man, their natural enemy, inhabit the surface of the Earth. The largest, though fewest in number, inhabit the ocean.

Linnaean Characteristics

Linnaeus divided the mammals based upon the number, situation, and structure of their teeth.

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