BONES OF THE HEAD 163 



22. The metatarsal bones of the hind legs. 



23, 23. The pastern of the hind feet, including the upper and 



larger bone (fig. 23), the lower pastern (fig. 25), and 

 the coffin-bone (fig. 24). 

 26, 26. The caudal vertebrae, or bones of the tail. 



BONES OF THE HEAD. 

 PLATE VIII, FIGS. 2 AND 3. 



The head contains the brain and other im- 

 portant organs of sense. It is divided by anato- 

 mists into two parts, namely, the skull and the 

 face. The skull, or cranium, is that portion in 

 which the brain is situate ; and the bones in which 

 it is enveloped are destined for its protection. 

 This division consists of nine bones : the two frontal 

 bones, a, a; two parietal, c, c; two temporal, d, d ; 

 the occipital, g ; the ethmoid ; and sphenoid : the 

 two latter are situate at the base of the skull, and 

 are not visible in a front view, but their position 

 will be seen in fig. 3, Plate HI, the ethmoid, or sieve- 

 like bone, immediately above k, and sphenoid, /. 

 These nine bones are separated in the foal at an 

 early period of its existence ; but soon after birth 

 they are firmly united together by the sutures, at 

 which parts they are so strong that fracture seldom 

 or never occurs there. 



There is a beautiful evidence of design in this 

 division of the head >into so many bones. When 

 the foetus of the foal in the womb first assumes a 

 form, and may be said to be in life, this portion 

 of the skull is merely a jelly-like consistence, which 

 is gradually changed into a harder substance, called 

 cartilage ; and previous to the birth of the animal 

 much of this cartilaginous substance is carried off 



