ELEMEXTS OF HIPPO LOGY. 



137 



on during the early spring, and he recovered from it before the 

 polo seasoned open. He played a fast game every fine day during 

 the season. His second attack came on during the next winter 

 and lasted several weeks. The following spring he played well 

 for two months, and then went permanently lame. 



Navicular dis- 

 ease does not 

 attack the hind 

 feet. (There are 

 but two cases on 

 record, according to 

 Moller, an eminent 

 German veterinar- 

 ian.) 



A ringbone 



(Figure 90) is a 

 bony growth on the 

 ankle. It is not a 

 disease in itself, but, 

 like bone spavin, is 

 a result of inflam- 

 mation in bone- 

 producing tissues. 

 Ringbones are 

 caused by blows, 

 sprains, overwork, 

 too fast work on 

 hard roads, jump- 

 ing, and the like. Horses whose pasterns are too short and up- 

 right are more liable to the disease that causes ringbone than 

 those with long, elastic pasterns. 



The first symptom is lameness. A puff, hot and harder 

 than the ordinary wind-gall, is noticeable. The ringbones that 

 develop under the extensor tendon or near the navicular joint 



Figure 90. 



