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described, being common to both, the plantar arteries send out 

 many branches to the neighboring parts. 



" The first of importance after a few small vessels about the 

 fetlock is called by Mr. Percival, the perpendicular artery, and 

 rises about half way down the os suffraginis, and takes its 

 course forwards and downwards to the coronary substance 

 where it anastomoses with its fellow and forms an arch called 

 the superficial coronary from whence proceed about eighteen 

 small descending arteries whose office it is to secrete the crust. 



" The second branch of importance is the transverse artery, 

 which crosses over to the front of the os coronae, underneath 

 the extensor tendon, and joins the corresponding branch from 

 the other side, forming the Superior Coronory circle, which 

 gives off numerous small vessels, some of which, passing down- 

 wards communicate with the inferior coronary artery before 

 described. 



" Thirdly, the plantar arteries, having given off these vessels 

 anteriorly distribute others posteriorly, the first of which is the 

 artery of the frog, which rises opposite the pastern joint, and 

 enters obliquely the substance of the sensitive frog, where it 

 divides into two branches, one going to the toe, and the other 

 to the heels of the frog, the latter of which sends branches to 

 the cartilages. 



" Fourthly, just as the main trunk reaches the coffin-bone, a 

 Targe branch, the lateral laminal, is given off, which enters the 

 foramen in the wings of the bone, and then winds around it in 

 a groove to the front of the foot sending branches in every 

 direction to the sensible laminae, and then enters by a smaller 

 foramen in the antero-lateral part of the bone and joins the 

 circulus arteriosus within it. From this artery a branch is 

 given off which joins the circumflex. 



"The Circulus Arteriosus presents a corresponding course 

 within the bone, to that described by its external border, and 

 gives rise to two sets of vessels : 



" First. — The Anterior Laminal Arteries, very small and 

 numerous branches which proceed through the foramina of the 

 coffin-bone and are distributed on the laminae. 



