MAN, 
is not crossed, degenerate into French 
horses in the second, or at latest in the third 
generation. 
The effect of food on the body is very 
obvious in tlie well known fact of several 
singing birds, cliiefly of the lark and finch 
kind.H, becoming gradually black, if they are 
fed on heinp-seed only. The texture of the 
hair has been changed, in an African sheep 
brought into England, from the coarse na- 
ture of that of the camel, to considerable 
softness and fineness, by one year’s feeding 
in the pastures of this country. The influ- 
ence of the same cause on the stature and 
proportions of the body is shewn in the 
horse, which grows to a large size in the 
marshy grounds of Friesland, while on stony 
soils or dry heaths they remain dwarfish. 
Oxen become very large and fat in rich 
soils, but are distinguished by shortness of 
the leg ; while -in drier situations their 
whole bulk is much less, and the limbs are 
stronger and more fleshy. I do not advert 
to the well-known differences of flavour and 
weight produced by different food. 
Mannev of life. Under this head we in- 
clude all those cattses, which can act on the 
animal economy besides climate and food ; 
and which, by their long continued influ- 
ence on the body, effect considerable 
changes in it. Culture and the power of 
habit are the most efficacious of these, and 
exert a very powerful and indisputable 
action on our domestic animals. Observe 
the striking difference pf form and propor- 
tion between the horse trained in the ma- 
nege, and the wild, untaught, and unbroken 
animal. The latter bites rather than kicks ; 
while the former, reined, and armed with 
iron shoes, uses these as his means of offence. 
The ass in its wild state is remarkably swift 
and lively, and still remains so in -his native 
countries in the east. The argali, or wild 
oi'iginal of the sheep, is covered with hair 
instead of woo! ; and the bison, or wild ox, 
has a long flowing mane, hanging almost to 
the ground. IMost of the mammalia, which 
have been tamed by man, betray their sub- 
jugated state, by having the ears and tail 
pendulous. In many the very functions 
of the body, as the secretions, generation, 
&c. are greatly changed. The domestic 
sow produces young twice a year, and the 
wild animal only once. 
Tire domestic pig acquires a vast accumu- 
lation of fat under the skin, which is never 
seen in the wild animal, which on the con- 
trary possesses a soft downy hair among its 
bristles, speedily lost in the tamed indivi- 
duals. The domesticated animals become 
liable to produce monstrous fetuses, and are 
exposed to new and numerous diseases : 
their bodies are even invaded by new kinds 
of worms , of which the hydatids in swine, 
forming what is commonly called the 
measles, are an indubitable instance. 
The three causes now mentioned produce 
their effect in changing the original charac- 
ter of the animal, and giving origin to a va- 
riety, only after a great length of time, and 
a continued action through several genera- 
tions. But these changes are communicat- 
ed much more quickly by the process of 
generation. When two varieties copulate 
together the offspring resembles neither pa- 
rent wholly, but partakes of the form and 
other peculiarities of both. This cannot 
with propriety be termed hybrid generation ; 
as authors apply that expression to the pro- 
duce of the copulation of different species, 
as of the horse and ass, &c. In this sense 
hybrids are never produced in the Iniman 
species: for although we read various in- 
stances of men and women having com- 
merce with animals, there is not a shadovr 
of reason for supposing that such copulations 
ever produced an offspring. Breeding from 
different varieties has a great effect in 
changing the colour and form of the animal 
produced ; and hence this method of im- 
proving and ennobling the mce is practised 
with great effect in the domestic animals, 
particularly-the horse and sheep. 
It seems even possible that a disposition 
originally morbid may be transmitted by 
generation, and acquire a permanent cha- 
racter. The peculiar whiteness of the skin, 
with red colour of the eye, occurring in the 
rabbit and ferret, and various other animals, 
as w'ell as in the Albino of the human race, 
appears in the first instance to be a moi bid 
affection of the body ; and when it occurs 
in one or two instances only, in the human 
subject, has the appearance of a leprous 
cachexy. But, in the animals just mention- 
ed, all the unnatural characters have been 
lost, and it is established as a permanent 
variety. We have, moreover, many facts, 
shewing that, in some cases, casual mutila- 
tions are fransmitt^d to the offspring: as 
want of tail in a cat or dog. (Philosophical 
Magazine, vol. iv. p. 2. Anderson’s Re- 
creations, vol. i. p. 69.) Tile Jews are fre- 
quently born with so little foreskin, that it 
is hardly possible to circumcise them : this 
they call being born circumcised. (Philo- 
sophical Magazine, vol. iv. p. 5.) 
In applying tlie reasonings derived from 
