282 WINDGALL. 



wardly, the cavit}^ of the tumour necessarily undergoes, yet does 

 not this cavity ordinarily become filled up and obliterated, but 

 continues, greatly reduced of course in dimension, to exist and to 

 contain fluid. This fluid may be but the natural secretion altered 

 in colour and consistence ; on the other hand, when the tumours 

 experience a repetition of injury from continued stress and strain 

 upon them, coagula of blood may be found mingled with the secre- 

 tion, exhibiting together that grumous character Gibson called 

 " corrupt jelly." In windgalls that have become not only solid, 

 but, from their long duration and chronic character, firm and hard 

 to the feel, is sometimes found, according to Hurtrel d'Arboval, a 

 white chalky matter (semhlahle a du pldtre); though, according to 

 him, this only occurs in cases in which the joints and tendons have 

 become stiff". 



Our esteemed coadjutor, Leblanc, who has made these morbid 

 changes his study, says, in giving an account of them, that he has 

 observed the synovial membranes to lose their transparency and 

 become variously clouded ; in the same articulation some portions 

 of the membrane being of a vermilion red, while others exhibited 

 a cherry red, a deep red, a yellow, and now and then a black 

 aspect — such changes being particularly observable about the 

 synovial fringes in the joint. Frequently, gelatiform infiltrations 

 are observed underneath the membrane, within the fringes and the 

 cellular tissue by which they are surrounded; veritable false 

 membranes of greater or less extent are likewise to be seen within 

 the articular capsules. These membranes, adherent sometimes in 

 places, at other times quite free, present great diversity of tinge 

 and consistence : frequently they exhibit an analogy to the fibrine 

 of agitated blood ; at another time they preserve the aspect of 

 highly smooth, white, hard, and lenticular bodies, floating at large 

 in synovial secretion. In inveterate windgalls which are fully 

 developed, and whose parietes, formed into a multitude of little 

 caverns as it were, have become cartilaginous or even osseous, 

 the synovial membrane and articular cartilages are destroyed, and 

 the surfaces of the bones worn as if from radiated motions. Such 

 wear of the cartilages and bones is likewise to be observed in old 

 horses in whom there is even no suspicion of joint disease. The 



