THE SKELETON. 



47 



surfaces for articulation with the ilium. This expansion 

 appears to be a modified transverse process. Prominent 

 transverse processes also project from the caudal angles. 



The caudal vertebrae vary greatly in number. Accord- 

 ing to Mivart, there are only four in the Manx cat; and 

 according to Jayne, there may be as many as twenty-six in 

 some varieties of the common cat. The transverse processes 



FIG. 26. CAUDAL ASPECT OF 

 FOURTH LUMBAR VERTEBRA. 



a, Accessory process ; cr, centrum 

 or body ; pa, pedicle ; tr, trans- 

 verse process; s, neural, canal ; 

 sp, spinotis process ; zg, the 

 mammillary process of the an- 

 terior articular process ; am, 

 lamina ; pz, articular process. 



FIG. 27. DORSAL ASPECT OF THE 

 SACRUM. 



fl, Floor of the neural canal; fr, 

 dorsal aperture of the inter- 

 vertebral foramen ; It, lateral 

 mass ; pzg, posterior articular 

 process ; sp, spinous process ; si, 

 auricular surface for articula- 

 tion with the ilium; tr, trans- 

 verse process; zgt, tubercle 

 formed by fusion of the artic- 

 ular processes; sg, anterior 

 articular processes. 



and articular processes become less prominent from the 

 third vertebra to the eighth or ninth, where they are. present 

 only as slight ridges. The spinous process is present in the 

 first three, but dwindles to a ridge in the fourth. The first 

 six or seven elements possess a neural arch which more 

 distally loses its roof, making the neural canal a mere 



