Chap. VI. The Jmtomy of a HOKSE. 95 



itn firft Vertebra^ and its other Procefles are either very 

 fmall, or very obfcure. On each Side, towards its Edges, 

 there are certain Sinuses to which tlie Haunch-bones adhere 

 by an intervening Cartilage. It has fix Fertel?ne-, its Spines 

 grow gradually lefs the nearer they approach the Rump, as 

 iheZ-^ff/'^^iJ^r^ themfelves do alfo. The Spinal Marrow has 

 likewife a Pailage in it, as in the other Vertebra^ out of 

 which there are feveral lefler Perforations for the Egrefs of 

 the Nerves. 



The Rump-bones are in number eighteen, The Rump, or 

 and are join'd to each other by an interven- ^''• 

 ing Cartilage or Griftle ; but fo loofely, that a Horfe can 

 move his Tail which way he pieafes ; thcfe have no Hol- 

 lownefs in them, only the uppermoft has a fmall Cavity 

 that receives the Procefs from the iaft Bone above defcribed j 

 they are foft and fpongy, and therefore the better adapted 

 to Motion, as they are alfo from their Make, growing gra- 

 dually lefs, until they end in a fmall pointed Cartilage. 



§ VII. Of the Olla Innominata, divided irits the Hip^ 

 Haunch, d?id Share-bones. 



The OJpi Innominata are feated on the Sides of the Os 

 Satrum. The firft is called the Os Ilium, q^ jj. 

 becaufe the Gut Ilium lies under it ; it is 

 the uppermoft and broadcft, and is joined with the Os Sa- 

 crum by a true Suture ; it is fomewhat fcmicircular, be- 

 ing convex and uneven on its OutfiJe, which is called its 

 Dorfum, or Back and Concave, and even on its internal 

 Side, which is called its Cojia ; and that Part by which 

 it is joined to the upper Vertebra of the Os Sacrum, is 

 called its Spine, or Edge. 



Its Spine is, in many Places, rough and uneven, there 

 being feveral Mufcles that take their Origin from it, as 

 alfo from its Dorjuni^ or back Part, which is in Lke man- 

 ner accommodated for the fame Purpofe. 



The fecond is called the Os Pubis, or Os p f 

 Share-bone, which forms the inferior and 

 Fore- part of the OJ/a Innominata ; it is joined to its Fellow 

 by an intervening Cartilage, and forms the Fore-part of 

 that Cavity, in human Bodies, and is called the Pelvis y or 

 Bafon. It is perforated with a very large Hole, and on its 

 inner and hinder Side, has two Procefles, from whence the 

 cavernous Bodies of the Yard, and fome MufcleSj lake 

 their Original, 



