ON BREEDING, 
194 
by climate, yet we perceive a great difference between the tex¬ 
ture of the coverings of those who inhabit different zones. 
There is a considerable difference between the thickness of the 
skin of the cart-horse and that of the racer, and likewise be¬ 
tween the texture of the hair of the two breeds. 
Mr. Percivall* appears to consider that there is some con¬ 
nection between the cutis and the hair, as it respects its colour; 
“ for the skin,” he says, “ as well as the coat of a black horse, 
is coarser and thicker than that of a horse of the same breed 
of another colour; and it is rather uncommon to see a black 
racer, whereas the colour is predominant among our large heavy 
cart-horses.” Nature has kindly endowed animals that inhabit 
cold climates with a dense skin, as well as a thicker covering, to 
protect them from the severities of the climate. In northern 
countries the sheep are covered with thick fleecy coats, whilst in 
warmer climes the wool degenerates into coarse hair. 
The dogs of Baffin's Bay are protected from the severities of 
the weather by dense woolly jackets, and their skins are con¬ 
siderably thicker than those in the East Indies, who have 
scarcely any hair. The Arab horse is covered with a soft, 
sleek, and glossy coat, whilst the shelty of Scotland is en¬ 
veloped with long shaggy hair. Most animals that are exposed 
to the severities of the weather have their coats longer, and 
even of a lighter colour, in the winter than in the summer : this 
effect of temperature is very considerable in wild animals. The 
Siberian roe, and the squirrel of Danish Lapland, that are red in 
summer, become gray in winter. “ Wolves, and the deer kind, 
particularly the elk and the rein-deer, become light in the winter: 
the sable (m . zebellina) and the martin (m. martes) are browner 
in summer than in winterfThe same is remarked in horses 
who run at grass throughout the year: their winter coats are of 
a lighter hue than the short glossy covering which follows in the 
spring. This is very observable in those miserable starved horses 
that inhabit Dartmoor, in Devonshire, and Gossmoor, in Corn¬ 
wall, in the winter months: 
“ They change their hue, with haggard eyes they stare; 
Lean in their looks, and shagged in their hair." 
But this slight difference in colour appears, in some mea¬ 
sure, to depend not so much on any actual change which the 
hair itself undergoes, but only as far as the cold weather affects 
the secretion of that oily matter which anoints the stem of the 
hair, and gives the coats of those horses who inhabit warm 
climates that glossy and brighter hue. 
* See Percivalfs Lectures, vol. ii, p. 197. 
t Lawrence, quoted from Novae Species, Quadupedum, p. 7. 
