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cerebellum. The spinal cord, unlike the brain, is formed of an outer white 
portion and a central grey portion, the former made up of fibres, and the latter 
of cells and fibres. 
The two figures placed/at the beginning of this chapter are taken by the 
kind permission of Dr. J. McFadyean, M.B., C.M., B.Sc., from his valuable 
work on the “Anatomy of the Horse.” They will give our-readers a very 
good idea of the superior and inferior aspects of the horse’s brain. It will 
be seen that the encephalon, or brain of the horse, is an ovoid mass, which, 
when viewed on its superior surface, shews most posteriorly the continuation 
of the spinal cord, called the medulla oblongata, and in front of this, 
the superior surfaces of the middle and two lateral lobes of the cerebellum.. 
In front of the cerebellum are seen the two large cerebral hemispheres, 
which are separated from the cerebellum by a deep transverse fissure, 
into which the tentorium cerebelli passes. 
On the inferior aspect, we see that the medulla oblongata is prolonged 
beneath the cerebellum, and then becomes continuous with the cerebral 
hemispheres, by means of the crura cerbri, which are bounded in front by 
‘the two thick white cords, the optic nerves. The brain may be said to 
consist of three portions: (1) The isthmus of the encephalon (the 
prolongation of the spinal cord); (2) The cerebellum; (3) The cerebrum. 
For further details, vide Dr. McFadyean’s work, or Chauveau’s 
Comparative Anatomy. 
STRINGHALT. 
AFTER these preliminary remarks, we may at once proceed to describe 
the diseases of the nervous system of the horse, commencing with stringhalt. 
Stringhalt consists in involuntary convulsive motions of the muscles, 
generally those of one or both hind legs; but occasionally it is 
seen in the fore legs also. Generally speaking, however, it is confined to one 
of the hind legs; more rarely affecting both of them. Stringhalt is a 
common affection of the horse, and of necessity constitutes unsoundness, 
although many horses affected with this disorder are able to do their work 
exceedingly well. We have a chestnut horse at the present time, and have 
seen numbers of others, which do their work every whit as well as horses 
in all respects healthy. In severe cases, stringhalt is evident to the observer 
at every step taken by the animal, while in cases not so marked, the affection 
can only be noticed at longer or shorter intervals. The animal may proceed 
a few yards in a normal manner, and then suddenly snatch one or both of his 
hind legs from the ground convulsively, with a. sudden jerk, and bring it 
down again with unusual force. 
' Stringhalt often becomes worse as time passes on, but it may remain in - 
pretty much the same condition for some years. We have often observed 
that it improves as the general health and condition of the animal improve, 
and becomes worse when the animal is worked too hard, or when from any 
other cause he is out of condition, As, in many instances, stringhalt 
H 
