572 , PROF. ST. GEORGE MIVART ON THE 
twenty-fifth vertebre may be opisthoccelous; a median subvertebral process may be 
formed, of bent-down lateral hypapophyses conjoined, as in Plotus; lateral acetabular 
fossa subtriangular or quadrate, but never enormous in size; supraacetabular fossa 
present or absent; always a marked interval between lumbar and caudal vertebrae 
through non-development of parapophyses; sacral vertebree distinct or not so. Pelvis 
including from fifteen to seventeen vertebre; ilia not meeting at an acute angle; no 
conspicuous ilio-pectineal processes ; ilia not flattened against the postacetabular verte- 
bre; acetabula, preaxiad to the antero-posterior middle of the pelvis; ischia and ilia 
largely united postaxially; pelvis more vertically extended behind than in front of 
acetabula; postacetabular part of pelvis broader transversely than the preacetabular 
part; ilio-caudal spine present or absent; preacetabular parts of ilia meeting in a 
median dorsal ridge; dorsum of postacetabular part of ilium not high, convex and 
broad. Sternum twice as long as broad, or else but very little longer than broad ; 
furcula ankylosed or not; only one lateral xiphoid process on each side. 
DESCRIPTION OF THE PLATES. 
(In Plates LV., LVI., LVII., & LVIII., the following letters have throughout the 
meanings here given.) 
ac. Preaxial surface of centrum. 
az. Preezygapophysis. 
Catapophysis. 
c’. Ridge extending postaxially from catapophysis. 
eg. Groove internal to catapophysial ridge. 
d. Diapophysis. 
jf. Foramen in catapophysial ridge. 
g. Groove external to catapophysial ridge. 
h. Surface for head of rib. 
hp. Hyperapophysis. 
Small process, preaxial to hyperapophysis. 
hy. Hypapophysis. 
Lateral parapophysial ridge. 
tz. Interzygapophysial ridge. 
m. Metapophysis. 
ns. Neural spine. 
o. Odontoid process. 
of. Foramen for odontoid process. 
p. Parapophysis. 
