D/S^ASJSS d» THE POOt. ^67 



aidmbrane secreting the horn. The part which forms the hoof> 

 wall is prolonged as a band around the upper margin of the 

 wall, and from the heels forward above the cleft at each side of 

 the frog. It is shaggy throughout with soft conical processes 

 (villi), from ^ to 2 lines in length, which extend into the homy 

 tubes and secrete them. The membrane forming the sole is 

 covered by similar villi which pass into the horny tubes of the 

 sole, and that covering the elastic frog hdLS corresponding but 

 smaller villi. Between the fibrous net-work and the inner sur- 

 face of the hoof-wall and bars, the mode of union is by a series 

 of 500 to 600 leaves (laminae) projecting on an average i| or 2 

 linesi and each having on its lateral aspects from 30 to 60 

 microscopic secondary laminse. These are interleaved with the 

 same number of primary and secondary horny laminse forming 

 an extent of connecting surface which would beget incredulity 

 if named. These inner fibrous and vascular laminse secrete the 

 homy laminse that are interleaved with them, besides giving ofif 

 an amount of moisture, which being absorbed by the cells of the 

 adjacent horny wall, serves to keep that soft, yielding, and 

 tough. So intimate is the union between each of these secre- 

 ting surfaces and the horn covering it, that the fibrous net-work 

 will often be torn from the bone, rather than the horn from the 

 sensitive parts. This is above all true of the laminse. This close 

 connexion further renders active inflammation in these structures 

 acutely painful, for there being no loose tissue to yield to the 

 exudation, it compresses these dense structures and violently 

 tears them apart. Thus extensive effusions of serum or pus 

 endanger separation and shedding of the hoof. A less acute 

 inflammation of any of those secreting surfaces leads to the pro- 

 duction of unhealthy horny growths. Thus disease of the 

 secreting membrane at the coronet will determine a bulging, 

 ragged, brittle line of horn from above downward on the hool- 

 wall, or, what is worse, a track or fissure extending to the quick. 

 Disease of the laminse will determine the formation of a great 



