ZONE

ZONE, in geography and astronomy, a division of the terraqueous globe with respect to the different degrees of heat found in the different parts thereof. The zones are

denominated torrid, frigid, and temperate. The torrid zone is a band, surrounding the terraqueous globe, and terminated by the two tropics. Its breadth is $46^\{\backslash circ\}\; 58\text{'}$. The equator, running through the middle of it, divides it into two equal parts, each containing $23^\{\backslash circ\}\; 20\text{'}$. The ancients imagined the torrid zone uninhabitable. The temperate zones are contained between the tropics and the polar circles. The breadth of each is $43^\{\backslash circ\}\; 2\text{'}$. The frigid zones are segments of the surface of the earth, terminated, one by the antarctic, and the other by the arctic circle. The breadth of each is $46^\{\backslash circ\}\; 58\text{'}$.

Mammalia. IS that part of Natural History which relates to Animals.

In order to abridge the study of zoology, many methods of reducing animals to classes, genera, and species, have been invented: But as that of Linnæus is undoubtedly the best, the most extensive, and the most generally adopted, we shall give a brief account of it.

Linnæus divides the whole animal kingdom into six classes. The characters of these six classes are taken from the internal structure of animals, in the following manner: