‘PARASITES—TUMORS, 277 
They do not yield to treatment. Sciatic neurotomy tried with. them has 
been. unsuccessful. 
LT, Springhalt.: 
This is an affection of the hind extremities which is frequent in horses 
and observed also in mules (Bassi), donkeys and cattle (Booth, F urlanetto). 
An analogous anomaly has been observed in the fore legs (Rigot, Delabére- 
Blaine, Goubaux, Hering, Siedamgrotzky, Moller; Jacoulet and Barrier). 
In some cases the trouble is hardly noticeable, in others it is so marked 
that the foot strikes forward against the abdominal wall (Fig. 63). Al- 
though ordinarily it develops slowly, accentuating itself by degrees, there 
Fig. 63.—Horse affected with Springhalt. (From photograph.) 
are individual cases in which it appears suddenly and without any ap- 
preciable cause. 
A functional anomaly symptomatic of various affections, it is character- 
ized by a sudden, convulsive-like flexion of a leg as it moves. Gener- 
ally it is more easily observed in walking, not so easily detected during 
a trot or gallop. Attimes it shows itself only at the beginning of work, 
and disappears when the animal is warm; at others it is less noticeable 
after a little exercise; again, it may last as long as the exercise or work 
is going on. 
Widely different opinions have been expressed in regard to its nature. 
Numerous authors think that it is the expression of articular Jesions. 
Carlo Ruini, Solleysel, Jean and Gaspard de Saulnier, La Gueériniére, 
