3G0 DISEASES OF THE SPINAL CORD AND ITS MEMl^lUANES. 



judgment. Where these alterations arc undou'ite.l they vary 

 from simply increased vascularity and appreciable thicken- 

 ing of the membranes, from adherent gelatiniform amorphous 

 exudations, or increase of the serous slightly coloured fluid, to 

 distinct induration of the meninges, and complete destruction of 

 the integrity of the intimate texture of the cord, which may 

 be not only pulpy but cliftiuent, and exhibiting serious altera- 

 tions in nerve tubes and cells, with the existence of other 

 elements, corpuscular, etc., the products of the diseased action. 

 These changes, Avhen occurring in the nervous tissue, are 

 usually most marked in the centre or grey matter of the cord 

 where the tissue is more vascular. This peculiar softening, or 

 ramollissement, although by many regarded as a condition 

 peculiar to nerve-structure, would seem to have nothing 

 specific connected with it, save so much as attaches to the 

 tissue which is invaded by ordinary inflammation. 



Symptoms. — Acute inflammation of the structures contained 

 within the vertebral canal may or may not be anticipated by 

 premonitory symptoms. As far as experience teaches it would 

 seem that such are more generally to be observed when the 

 inflammation is distinctly associated with the membranes of 

 the cord, and most likely to be absent when this morbid action 

 is exclusively or more extensively confined to the substance of 

 the cord itself Occurring prior to the paralysis, or loss of 

 control over the voluntary movements of the limbs, the great 

 diagnostic symptom in all cases, although its appearance may 

 in some be delayed, is spasmodic or clonic contraction of the 

 great muscles connected with the trunk and limbs. The animal, 

 we may be told, has been suddenly seized with cramp of his 

 hind limbs ; but this cramp, we may observe, is not uncon- 

 nected with constitutional disturbance, as in the condition 

 ordinarily recognised by that term. The limbs are lifted 

 rapidly from, and as rapidly placed u]Don, the ground ; and 

 although the movement evidently causes pain, the animal does 

 not seem able to control or discontinue it. At this early stage 

 there may be intervals of calm, and freedom from muscular 

 s[»asms ; only, however, to be succeeded by exacerbation of all 

 these functional disturbances. Perspiration plentifully bedcAvs 

 the body, the animal is restless, but the very movements he 

 executes only intensify the pain and muscular spasm. This 



