38 



THE SKELETON OF THE HORSE 



THE LUMBAR VERTEBRAE 

 The lumbar vertebrae (Vertebrae lurnbales) are usually six in number in the 

 horse. They are characterized by the size and form of their transverse processes. 

 The bodies of the first three are triangular on cross-section, and present a 



Spine 

 Anterior articular processes 



Arch 



Transverse process 

 Facet for head of first rib 



ns verse process 



/ 

 Body 



first rib ^"y^ 



Fig. 16. — First Thoracic Vertebra a.nd Upper Part of First Rib of Horse, Anterior View, (.\fter 



Schmaltz, Atlas d. Anat. d. Pferdes.) 



distinct ventral crest. From the fourth backward they become wider and flatter 

 and the ventral crest fades out. 



The arches of the first two or three are about equal in size and similar to that 

 of the last thoracic; from the fourth they decrease noticeably in breadth and height. 



The anterior articular processes are fused with the mammillary processes, and 



Mammillary processes 



Facet for head of rib' 

 Facet for tubercle of rib 



Intervertebral foramina 



Posterior articular processes 



Tubercle of rib 

 Head of rib 



Fig. 17. 



-Last Two Thoracic and First Lumbar Vertebr.e of Horse, Lateral View. 

 Atlas d. Anat. d. Pferdes.) 



(After Schmaltz, 



present superiorly concave surfaces for articulation with the posterior pair of the 

 preceding vertebra. The posterior articular processes project distinctly from the 

 arch at the base of the spinous process, and have ventrally convex articular sur- 

 faces, which fit into the grooved surfaces of the anterior pair of the next vertebra. 

 The transverse processes are large plates, flattened dorso-ventrally, which 

 project outwartl and usually curve slightly downward; their length increases to 



