On the Natural Provinces of the Animal World. 347 
principal elements of the most extended thermal springs, the 
sulphurets and the alkaline bicarbonates, have sufficed to pro- 
duce twenty-nine distinct mineral species, almost all crystal- 
lized, belonging to all the great families of the chemical com- 
pounds peculiar to concretionary beds, each of which has some 
representatives in my experiments. Means of synthesis 
equally simple, applicable however to compounds as variable, 
give certainly a great probability to the speculative ideas 
which have directed me in these researches. It will, more- 
over, be necessary to diversify them to a much greater extent, 
and we shall, in the same manner, have studied the different 
chemical agents, and the influences of every kind which can 
modify their effects ; we shall undoubtedly succeed in defining 
the probable condition of the formation peculiar to each class 
of metalliferous beds, and by tracing their origin, step by 
step, in the same order of systematic experiments, we may 
finally arrive at the crystallized rocks which associate them- 
Selves to these beds by methods and phenomena of continuity 
which it is impossible to mistake. 
On the Natural Provinces of the Animal World, and their 
Relation to the diferent Types of Man. By Louis 
AGASSIZ.* 
There is one feature in the physical history of mankind which has 
been entirely neglected by those who have studied this subject, viz., 
the natural relations between the different types of man, and the 
animals and plants inhabiting the same regions. The sketch here 
presented is intended to supply this deficiency, as far as it is possible 
in a mere outline delineation, and to show that the boundaries 
within which the diferent natural combinations of animals are 
known to be circumscribed upon the surface of our earth, coincide 
with the natural range of distinct types of man. Such natural 
combinations of animals, circumscribed within definite boundaries, 
are called faune, whatever be their home—land, sea, or river. — 
Among the animals which compose the fauna of a country, we find 
types belonging exclusively there, and not occurring elsewhere; such 
are, for example, the ornithorynchus of New Holland, the sloths of 
- * Dr Usher, Dr Nott, and G. R. Gliddon, on the Types of Mankind, 
