%z The Anatomy of a HORSE. Chap. VI. 



but grow extremely thin upwards, lying like two Scales on 

 the lower Edge of the Bones of the Sinciput. 



They have each of them two Sinus's, the outermofl being 

 the largeft, is lined with a Grillle, and receives the longer 

 Procefs of the lower Jaw. The other, or inward Cavity, 

 is common to the Temple-bone and Noll-bone. There 

 are alfo four Procefles belonging to each Temple-bone, viz, 

 that which in Man is called the ProceJJits StyloideSy or Pen- 

 like Procefs, though improperly in a Horfe, it being but 

 fhort. The next is called the ProceJJiis mammillaris, being 

 fbmewhat fliap'd like a Nipple. The third palling forwards- 

 fiom the Hole of the Ear to the Protuberance of the firft 

 Bone of the upper Jaw, and being joined to the !aft, forms 

 the Os Jugale\ or Yoke- bone. TThe fourth is the Procejfui 

 petrofus, or hard and uneven part of the Temple- bone ; 

 this,- being internal, jets out a pretty Way into the Infide 

 of the Bottom of the Skull, within v^'hich there are two Per- 

 forations 5 one to give a Paflage for an Artery, another for 

 the Auditory Nerve, mto the inner Cavities of the Ear, to 

 y^'it, the Tympanum, Labyrinth, and Cochlea. 



This Procefs has alfo on its outfide three Perforations, or 

 Holes ; the firft called the Meatus auditorius, or Auditory 

 Paflage ; the fecond is that thro' which the Jugular Vein 

 enters into the inner Cavities ; the third is feated between 

 the Maimnillary and Styloid Procefles, ending in that Paf- 

 fage that goes from the Ear to the Mouth. As to the little 

 Bones that are contained in the Cavities of this Procels, viz, 

 the Incu:, Malleus, Stapes, and Os orbicularc, which, 

 with thofe already defcrib'd, make up the whole Number of 

 the Bones proper to the Skull, having taken notice of them 

 already in another Place, I fliall therefore pafs on to thofe 

 "which are common to the Skull and upper Jaw ; and thefe 

 are in Number three, namely, the Os Sphenoides, or Wedge- 

 like Bone, the Sieve-lih Bone, and the Toke-like Bone. 

 'The Wedze-like '^^^ Wedge-like Bone is fo called from 

 Bone '^^^ being placed like a Wedge between the 



Bones of the Skull and the upper Jaw ; it is 

 joined before to the Frontal Bone, and behind to the Occi" 

 pital, its Sides to part of the Petrofiim above, and below 

 ■ to fome of the Bones of the upper Jaw and Palate. 



It has feveral Procefles, fome external, and fome internal ; 

 as alfo divers Cavities, two of which are common to it and 

 the Temple-bones, and the Bones of the Sinciput. Its Holes 

 are about feven on each fide ; one of which gives a Paflage 



to 



