PLANTAR SYSTEM. 425 



and eversion ot the outer flakes of horn around its junction with 

 the wall below. Externally, it assumes the same character as 

 the wall below it; but its internal surface is altogether different. 

 Instead of possessing laminae, the surface is smooth and uni- 

 formly excavated, being moulded to the form of the sensitive co- 

 ronet, and everywhere presenting numerous pores for the purpose 

 of receiving the secreting villi. Superiorly, the coronary bonier 

 presents two edges, having a groove between them for the recep- 

 tion of the terminating border of the cutis. It is this groove 

 that marks the reception of the coronary border into two parts : 

 the internal edge belonging to the inner part, which is the 

 beginning of the wall itself; the external edge to the white band 

 by which the other is embraced, and to which Mr. Clark has 

 in particular drawn our attention, under the appellation of Coro- 

 nary Frog- band. This covers the proper or veritable coro- 

 nary border of the hoof; having, through its fibres, which are 

 very fine, a sort of dove-tailed connexion with it. As it recedes 

 backward, it grows broader to that degree, that its breadth at 

 length becomes doubled ; being about half an inch broad in front, 

 and one inch behind. It is thickest around its middle parts ; 

 its inferior edge, like the superior, becoming attenuated, until it 

 grows so fine as to end in imperceptible union with the substance 

 of the wall, giving it its beautifully polished surface : from the 

 heat, however, to which the hoof is artificially exposed, the thin 

 part below the coronet often grows arid, splits from the crust, 

 and becomes everted ; turning at the same time, in consequence 

 of dryness, of a whitish complexion. Posteriorly, we find it 

 continued round the heels of the wall and frog, and from thence 

 across the back of the cleft, forming altogether a complete cir- 

 cle, and everywhere shewing itself to be the medium of connexion 

 between the skin and the hoof. It has been already stated that 

 the cutis terminates in a circular border, let into a groove around 

 the summit of the wall : the cuticle, however, does not end here — 

 it is continued down ; in fact, we trace it to the horny band we 

 have been describing, the one being continuous in substance with 

 the other. Indeed, the only detectible differences in them are, 

 that one is thicker than the other, and grows hard, and dry, and 

 white, from the effects of heat upon it from without, and the want 

 of moisture from within. This cuticular origin and assimilation 

 may be demonstrated in the putrefied foot ; or, better still, in the 

 foot of the foetus. The band is broader at the heels than else- 

 where, in consequence of the greater breadth of exposed cutis at 

 those parts. In its texture it is fibrous, and its fibres pursue the 

 same direction as those of the wall, from which they differ only 

 in being of a finer texture. Mr. Bracy Clark appears to enter- 

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