BACKBONE 



423 



posterior articular process or postzygapophysis which fits on to the 

 corresponding prezygapophysis of the next vertebra, while at the 

 side a transverse process projects, and at each end there is an inter- 

 vertebral notch for the passage of a spinal nerve, the adjacent 

 notches of two vertebrae enclosing an intervertebral foramen. 



ver, c. 



pz.. 



0(1. p. 



Fig. 336. — Vertebrae of a rabbit. 



A, Atlas, from above ; B, axis, from the right ; C, one of the middle cervical vertebras, from in front ; 

 D, fourth thoracic vertebra, from the right ; E, second lumbar vertebra, from the right ; F, the same 

 from in front. 



aps., Anapophysis ; az., prezygapophysis ; cm., centrum ; c.r., cervical rib, fused to transverse process and 

 centrum ; ep., epiphysis ;/., facet on axis for articulation with atlas ;/'., corresponding facet on atlas ; 

 /"., facet on atlas for odontoid process ; f.c, f.c'., demi-facets for heads of ribs ; f.t., facets for tuber- 

 culum ; hps., hypapophysis ; mps., metapophysis ; n.a., neural arch ; n.s., neural spine ; od.p., odontoid 

 process ; pz., postzygapophysis ; tr., transverse process ; v.c, vertebral foramen ; ver.c, foramen of 

 transverse process. See also Fig. 346. A and B. 



Each end of each centrum, with the exception of the first two, 

 is fiat, a shape known as amphiplatyan, and against it in the 

 young rabbit is a thin bony disc or epiphysis, which fuses with it 

 when growth is complete. The general characters of the vertebrae 

 of the rabbit may be well studied in that known as the second 

 lumbar (see below), but this and the others show many peculiar- 

 ities. The backbone is divided into five sections, the neck or 



