C^AP. VI. The Anatomy of a HORSE. %i: 



they are joined to the Temple- bones. They are frftooth 

 on their Outfide, but inwardly uneven, having feveral Ca- 

 vities to which the Dura Mater adheres by the Sides of 

 the Sagittal Suture ; as alio feveral long and winding In- 

 fcriptions, or P'urrows, form'd by the Branches of the /v- 

 ternal Jugulars^ in their Paflage to the Brain. Thefc 

 Bones have allb feveral Perforations ; fome of which go 

 quite through, others piercing only the upper Table, for 

 the Entrance of thofe Veflels which run between its Plates. 

 The Orr//)//^/, or Noll- bone, which makes q-^^^ Noll-boue 

 the hinder and lower Part of the Head, and .^^,y^;^ j,^ Parts'. 

 middle of the Bafis of the Skull, is the 

 hardeft of all the Bones of the Skull, excepting the Os Pe- 

 trofum of the Temple-bones, being very thick at Bottom, 

 where the two Sinus's of the Dura Mater are joined. 

 At the Sides of the great Perforation, through which the 

 Spinal Marrow defcends, it is fomewhat thin ; but that 

 its Thinnefs might be no Prejudice to it, it is llrengthenM 

 by a large Prominence, which afcends from the faid 

 Perforation quite to Its upper Part. By this Prominence 

 the two Protuberances of the Cerebellum are alfo diftin- 

 guilhed. 



This Bone is in a Horfe ftve-corner'd, and has feveral 

 Channels, or Si;ius'sy two of which, being pretty large, 

 receive the Protuberances or Bunchings of the Cerebellum, 

 or After-brain ; others receive fome of the Convolutions of 

 the Brain itlelf, and fome, the two Sinus's of the Dura 

 Mater, that they might not be comprefled or hurt for 

 Want of a proper Cavity to lie in. 



It has alfo divers Procelles, four of which, being covered 

 with a fmoolh Griftle, are received into the Si?ms's of the 

 lirft: Vertebra of the Neck ; but that which goes between 

 the Protuberances of the Cerebellum^ is the nroft confider- 

 able. It is perforated in five Places, for the Paflage of fe- 

 veral Vellels,- befides the large Hols through which the 

 Medulla goes into the Spine of the Neck.' 



The lalt of the proper Bones of the Skull, iT^e Tempu- 

 are the Temple-bones, which are feated on ■P''*^^ '^'^^ 

 each fide of the Head, reachiiig to the Bot- thnrjroct^^ 

 torn of the Ears. Their Figure is on their '"''^^'^^^^^ 

 upper fides femicircuLar, but below they are rugged and 

 unequal, like a Rock ; from whence, and from their Hard- 

 nefs, the Temple-bone has alfo obtained the Name ot Oi 

 Petrofum, Thefe Bones are very thick at their Bottom, 



G bus 



