52 ANATOMY OF THE RABBIT. 
region is reduced to a vestigial Coccyx, consisting of coalesced 
vertebrae. 
The individual vertebra is made up of a more massive ventral 
body, upon which is set a bridge of bone forming the arch. Both 


fi/ 
ons 
Fic. 25. Mid-lumbar vertebrae of bear (A, fifth), rabbit (B, fifth), and man (C, 
third): a, inferior articular process; c, body; m, mamillary and superior articular pro- 
cess; Ss, spinous process; t, transverse process. 
body and arch bear processes which reach into the surrounding 
muscles, and serve for their support. The principal processes are 
THE FORMS mid-dorsal or spinous, 
OF VERTEBRAE, !ateral or transverse, 
and, in the lumbar re- 
gion, dorsolateral or mamillary. Gener- 
ally speaking every vertebra has three 
principal functions—to support the body, 
to protect the spinal cord, and to offer 
support for muscles. 
Any vertebra of the rabbit may be com- 
WiG.26. Lumbar-vertebra of Dated with the: corresponding ‘vertebrasot 
four-day ‘ord rabbit; tulaee any mammal or in a general way with those 
of any vertebrate. The fifth lumbar 
vertebra of the rabbit, for example, would be found distinguished 
by the great development of its processes, since the latter support 
powerful muscles used in leaping. The corresponding human 
vertebra, or the third as functionally more nearly equivalent, is 
weak in muscular expansion, but its body is massive for purposes of 

