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disease, and of conversion of the membrane into cartilage. 

 The lack of a due secretion of synovia leads to consequences 

 of a most serious nature to joints. Abrasion and absorption of 

 the articular cartilages is the first result, leading in many cases 

 to a species of dry-rot in the bones. A deep furrow may be 

 plowed into the articular cartilage, as is often met with in the 

 astragalo-tibial articulation of the hock-joint, where there is 

 lameness without any palpable or ocular evidence of spavin, 

 incipient, or otherwise. The phrase occult spavin is often made 

 to do duty for occult lameness, arising from the cause alluded to. 

 This lesion will receive fuller consideration under the head of 

 Springhalt. 



