260 ROAD, TRACK, AND STABLE. 
widely distributed, not confined even to the salubrious 
region of Arabia. 
But there is one argument in favor of the Arabian 
being the primitive horse, which I have chanced upon, 
and which I here present to. those enthusiasts who 
will appreciate it. There is a conjecture of Darwin’s 
that the dark stripe running along the spine of some 
horses, and occasionally extending to the shoulders 
and legs, may indicate a “descent of all the existing 
races from a single dun-colored, more or less striped 
primitive stock, to which our horses occasionally re- 
vert.” In the Cleveland Bay family this dark stripe, 
or “list,” is valued as a mark of pure blood; it is 
found also in the Exmoor breed of ponies, and in some 
other strains. 
Now Major Upton reports an observation made by 
him upon horses in the desert as follows: “A line 
somewhat darker than the general color of the animal 
is to be seen in col¢ foals, running in continuation of 
the mane along the spine, and to be traced for some 
way even among the long hair of the tail. I never 
saw it in a filly. ... It can be traced in old horses 
and in those of a very dark color. . . . It appears as 
the first or primitive color of the animal, which tones 
away by almost imperceptible degrees from the back 
to the belly; it may be seen in lines on the males of 
other wild animals. At certain seasons, and as the 
horse ages, and dependent also in some degree on his 
condition, the dark color spreads over the shoulders 
and upper parts of the body,... as if shaded with 
black.” To be sure, Major Upton states that this phe- 
nomenon is ‘totally different from the markings of 
the zebra, quagga, or any of the hybrids ”; but never- 
