CONCLUDING OBSERVATIONS. 361 
of course, be our guide in the classification of animals, so 
that it may be a natural and not an artificial classifica- 
tion, In studying nature we should always endeavor to 
read correctly the traces of the mind of the Creator. 
628. The distribution of animals in the various regions 
of the earth is a very interesting subject, but my limits 
will allow of but a brief notice of it. Man is the only 
animal that is found in every part of the earth. He is 
thus a cosmopolite, because he has a mind that can con- 
trive clothing and habitations suitable to every variety 
of climate. Next to him in general diffusion are some 
of those animals which are domesticated by him, and also 
some which follow him and dwell in his habitations, as 
the mouse, the rat, the fly, etc. Most animals are limited 
to certain regions, differing, however, in the extent of 
their diffusion—some having a wide range, while others 
are confined to comparatively narrow limits. Those an- 
imals which are found in any particular region or coun- 
try are said to constitute its Fauna, as the flowers found 
there make up its Flora. We speak of the Faunas of 
the arctic, the temperate, and the tropic regions. Then, 
also, we subdivide these into Faunas of portions of these 
regions of greater or less extent, according to circum- 
stances. The dividing lines between the different zoo- 
logical provinces thus marked out are by no means im- 
passable boundaries, for there is generally a mingling of 
animals near the borders of two adjacent Faunas. Thus, 
although the Fauna of the United States and that of the 
region west of the Rocky Mountains are very distinct, 
yet these mountains do not effect an entire separation, 
for some animals of either Fauna are found on both sides 
of the range. 
629. The Faunas of the arctic region have compara- 
tively few species, but the number of individuals of each 
is often immense. Especially is this true of the fishes and 
the birds. The birds are mostly of the aquatic tribes— 
gulls, cormorants, ducks, petrels, etc. All the animals 
