| APRIL 21, 1904] NATURE 93 
Nn 
| reaches a considerable length. Owing to the great width | her head low and to one side, made a rush for the shelter 
|of the middle portion the one half of the mane generally | of an adjacent wood; the half-bred colt—prevented by her 
falls to the right side, the other to the left. The front | \Celtic blood from running away—tried in vain one position 
after another, and long before the storm 
ceased looked thoroughly miserable and 
began to shiver as if chilled to the bone. 
It hence follows that the tail-lock is 
not, as I at first assumed, an inherit- 
ance from a primitive ancestor akin to 
the wild horse, but a highly specialised 
structure which eminently adapts the 
Celtic pony for a sub-Arctic environment. 
I need hardly say the caudal fringe is 
not a product of artificial selection, for 
even in Iceland, where it reaches its 
maximum development, neither its 
existence nor its use has, so far as I 
can gather, ever been referred to. It 
need only be added that to maintain 
a tail-lock of this kind it is necessary 
that the short wiry hairs of which it con- 
sists require to be renewed once a year. 
In separating asses and zebras from 
horses, stress has hitherto’ been laid on 
the difference in the mane and tail, and 
especially on the absence of hind chest- 
nuts. As already pointed out, the wild 
horse during summer in its mane and 
tail agrees with asses and zebras. The 
mane and tail are hence no longer of 
specific importance. This is also true 
of the chestnuts, for in the Celtic pony, 
as in asses and zebras, the hind chest- 
nuts (hock callosities) are completely 
part of the mane hangs down over the face to form a fore- | absent. In the wild horse, as in the vast majority of heavy 
lock (Fig. 5). : and cross-bred horses, the hind chestnuts reach a consider- 
The most remarkable feature of the Celtic pony is the | able size, but in asses and zebras and the Celtic pony I 
tail. To begin with, the dock is relatively very 
short—so short that one is apt to suppose it has 
‘been docked. ‘The distal two-thirds of the dock 
carries long dark hairs, the majority of which 
continue to grow until they trail on the ground. 
During winter and spring the proximal third of 
the dock—about 4 inches—carries stiff hair from 
3 to 6 inches in length, which forms what may be 
known as a caudal fringe or tail-lock (Figs. 5 and 
6). In the case of Arabs and other semi-tropical 
horses the first 1 or 2 inches of the dock are usually 
covered with short fine hair like that over the 
find-quarters, but in the Celtic pony fine wiry 
hairs from 4 to 5 inches in length extend right up 
to the root of the dock under cover of the body 
hair of the croup. The most distal hairs of the 
tail-lock overlap, but are quite distinct from, the 
Jong persistent hairs carried by the lower two- 
thirds of the dock. The hair in the centre of the 
fringe of the same colour as the dorsal band 
(Fig. 6), projects obliquely backwards; the hair 
at the sides is light in colour and projects obliquely 
outwards. The presence of this very remarkable 
bunch of hair at the root of the tail was quite in- 
comprehensible until I noticed what happened 
during a snowstorm. ‘The inoment the storm set 
in the pony orientated herself so that the snow was 
driven against her hind-quarters. In a few 
minutes the lock of hair was spread out to form a 
disc, to which the snow adhered, and thus pro- 
vided a shield which effectively prevented the flakes 
finding their way around the root of the tail, where 
they would have soon melted and effectively chilled 
the thinly clad inner surface of the thighs. Pro- 
vided with a caudal shield, long thick hair over 
the hind-quarters and back, and a thick mane 
covering both sides of the neck and protecting the 
small ears, a Celtic pony is practically snow-proof. ; 
While the storm lasted the pony in question stood Photoyraph by G. A. Eavart- 
perfectly still, with her head somewhat lowered, Fic. 6.—Celtic pony, to show tail-lock in midwinter. 
save when she shifted her position as the wind 
veered from north-west to north. Very different was the | have failed to find any rudiments of hind chestnuts either 
Photograph ly G. A. Ewart. 
Fic. 5.—A typical Celtic pony in winter coat. (Note the ‘‘ beard,” forelock, and tail-lock.) 
behaviour of an Arab, and a thoroughbred Highland colt | before or after birth. Further, in the C ‘eltic pony the front 
close by. After trying various attitudes, the Arab, carrying | chestnuts are small, and, still more remarkable, the fetlock 
NO. 1799, VOL. 69] 
