PLATE LIV. 



Fig. 1. Posterior view of a dorsal vertebral spine, showing apical en- 

 largement. X %. 

 Fig. 2. Lateral view of three consecutive dorsal vertebrae, x %• 

 Fig. 3. Ventral view of left sacral rib. x %• 

 Fig. 4. Dorsal view of the same. 



