64 SCIENTIFIC HORSESHOEING. 



the perforatus and perforans, and one principal muscle, the front 

 extensor, straightens or thrusts the foot forward. (See Figs. 

 4 and 5.) 



Q. 9. What is the significance of their positions and inser- 

 tions ? 



A. Knowing the action of the bones to be straightforward 

 and back, we know that the muscles must act on the same line. 



Q. 10. What duty do the navicular and small sesamoids per- 

 form? 



A. They act as pulleys (and supports annexed to the joints) 

 in facilitating the gliding movements of the muscles which pass 

 over them. 



Q. 11. What do we understand by the "soft tissues" of the 

 foot? 



A. They comprise various organs of cartilage, fibrous or 

 elastic tissues for the development of other tissues, and for easing 

 concussion on the hard organs. 



Q. 12. What are the principal apparatuses thus referred to ? 



A. The lateral cartilages, the coronary and plantar cushions. 



Q. 13. What further do we know concerning them? 



A. The cartilages are pads at the sides of the foot, the 

 coronary cushion secretes the horny wall, and the plantar cush- 

 ion acts as a support to the back tendons. 



Q. 14. What are the " sensitive tissues"? 



A. The laminal or leafy tissue and the velvety tissue, 

 which are continuous with the membrane covering the entire 

 foot. 



Q. 15. What is the function of the laminse ? 



A. They form the connection between the internal foot and 

 the encasing hoof, by dovetailing into the horny leaves on the 

 wall, and thus support the action of the two parts. 



Q. 16. What of the velvety tissue ? 



A. This is the covering of the sole of the coflin-bone, the 



