422 MR. ST. GEORGE MIVART ON THE 
Its neural arch is united by suture to its fellows and to the centrum, and is antero- 
posteriorly contracted below, so as to have a large intervertebral opening both pre- and 
postaxial of it. 
The most preaxial part slightly rests on the postaxial extremity of the thirtieth 
vertebra. 
LATERAL ASPECT OF LUMBAR AND SACRAL VERTEBRA OF AN IMMATURE SPECIMEN 
(% natural size). 
1, Twenty-ninth (or second lumbar) vertebra; d', its diapophysis; s', its neuralspine. 2. Thirtieth vertebra. 
3. Thirty-first vertebra; p”, its posterior parapophysial projeetion, which concurs with the anterior (and 
smaller) parapophysial projection (p*) of the next vertebra to form an articular surtace for the ilium. 4. 
Thirty-second vertebra ; p* and p“’, anterior (preaxial) and posterior (postaxial) parapophysial projections ; 
the latter concurs with the anterior parapophysial projection (p°) of the succeeding vertebra to form an 
articular surface. 5, Thirty-third vertebra; p’ and p", its parapophysial projections. 6. Thirty-fourth 
od 
vertebra. 7. Thirty-fifth vertebra. 8. Thirty-sixth (or first sacral) vertebra; d*, its diapophysis ; 
p**®, its rib or capitulum, which has coalesced distally with the same parts of the two succeeding vertebrae. 
9. Thirty-seventh vertebra. 10, Thirty-eighth vertebra. 11. Thirty-ninth (or first sacro-caudal) ver- 
tebra; dp", its conjoined dia- and parapophysis. 12. Fortieth (or second sacro-caudal) vertebra. 
The diapophysis is inclined like that of the last vertebra, but has a flattened surface 
at its extremity; it is quite separate from the parapophysis, which is formed by the 
ventral part of the neural arch, and offers a rounded, flat, articular surface (fig. 59) to 
the ilium. This surface is very slightly reinforced by minute adjacent portions of the 
centra.of this and the preceding vertebra. 
The side of the centrum at its postaxial part exhibits a small neural foramen near its 
dorsal border and in front of a large parapophysial surface (fig. 59, p*), which this 
part of the centrum contributes towards the proper parapophysial surface of the next 
vertebra. 
Tue THirty-SEcoND VERTEBRA. 
This vertebra (figs. 59, 60, & 61, 4) has a spinous process at its maximum of deve- 
lopment and anchylosed to the adjacent spines. 
