THE SENSOR1AL FUNCTION. 



Ill 



lies beneath the uppor part of them. Lower down, and where the cavity of the 

 nose is to be defended, their union is sufficient, but far less complicated. Thus, 

 at first starting, there is an evident proof of design, an illustration of that 

 adaptation to circumstances which will again and again present itself in the 

 most interesting points of view. Peculiar strength of union is given where a 

 most important organ is to be defended the suture is there intricate and laboured. 

 Where less important parts are covered, it is of a far simpler character. 



Few things more clearly indicate the breed or blood of the horse than the 

 form of the frontal bones. Who has not remarked the broad angular forehead 

 of the blood horse, giving him a beautiful expression of intelligence and fire, 

 and the face gradually tapering from the forehead to the muzzle, contrasted 

 with the large face of the cart or dray-horse, and the forehead scarcely wider 

 than the face ? 



At/, between the frontal bones, is the pit or cavity above the eye, and by the 

 depth of which we form some idea of the age of the horse. There is placed at 

 the back of the eye, a considerable quantity of fatty substance, on which it may 

 revolve easily and without friction. In aged horses, and in diseases attended 

 with general loss of condition, much of this disappears; the eye becomes 

 sunken, and the pit above it deepens. It is said that some of the lower class of 

 horse-dealers puncture the skin, and, with a tobacco pipe or small tube blow 

 into the orifice, until the depression is almost filled up. This, with the aid of a 

 bishopped tooth, may give a false appearance of youth, that will remain during 

 some hours, and may deceive the unwary, but the trickery may easily be 

 detected by pressing on the part. 



These bones, however, are not solid, but a considerable portion of them is 

 composed of two plates receding from each other, and leaving numerous and 

 large vacuities or cells. These vacuities are called the frontal sinuses. They 

 are shown in the following cut. 



SECTION OF THE HEAD. 



\ 6 



a The nasal bone, or bone ot the nose. 



b The frontal bone. The cavities or cells beneath arc called the frontal sinuses. 



c The crest or ridge of the parietal bones. 



