EXPLANATION OF PLATE II. 



CURB AND SPAVIN. (Percivall.) 



Fig. 1. Curb. In this posterior view of the hind leg, from the point of 

 the hock to about one-third of the length of the cannon downwards, 

 is displayed a curb, in its ordinary chronic and permanent state, slit 

 open and dissected so as to develop its anatomy. 

 The subcutaneous cellular fascia, including the annular ligament {a a) 

 is dissected o£E and pinned back, in order to bring into view the 

 sheath of the flexor tendons in the thickened and callous condition 

 (b h) in which it is found in — which, indeed, constitutes the essence 

 of — chronic or prominent curb. The sheath has had a longitudinal 

 division made of it, and the divisions {b, h) separated, with the 

 view of better showing the augmentation of substance it has under- 

 gone, the consequence of disease originating in sprain. This division 

 and separation has brought into view also the bursal cavity through 

 which (the same as in the fore leg) the perforans tendon {c) plays, 

 in action. This is the cavity which is distended with fluid in 

 recent, and in some instance has been found so in chronic, curb. 



(fZ) The posterior side of the point of the hock. 



(e) The lower (sawn) end of the metatarsal bone. 



Fig. 2. Represents a spavin of unusually large size, and more prominent 

 and better defined than such tumors in general are. 

 a, The os calcis. 

 h, The large metatarsal or cannon bone. 



c, The small metatarsal or splent bone. 



d, The astragalus. 



e, g, The limits, superiorly and inferiorly, of the spavin tumor; whose 

 surface exhibits a knobby irregularity, and whose substance is osseo- 

 cartilaginous. 



/, Part of the periosteal membrane, in which the tumor is encased, 



dissected off. 

 p, A piece of whalebone inserted into the joint between the two flat 



cuneiform bones. 



