336 MR. W. H. FLOWER ON THE OSTEOLOGY OF THE SPERM-WHALE. 
The spinous processes progressively increase in height from before backwards. That 
of the first is a small irregular tubercle broader than long, and scarcely higher than that 
of the conjoined cervical vertebre. That of the second is still inconspicuous, but more 
compressed from side to side. The great antero-posterior width characteristic of the 
remainder begins to be seen in the third. The spines of the fifth, sixth, and seventh 
Anterior surface of the fourth dorsal vertebra and head of right mb. 
scarcely differ in form and dimensions, being, when seen from the side, nearly square. 
From the eighth a more rapid increase in vertical height takes place, until the last, 
by its elevation, narrowness at the base, and expansion at the extremity in the antero- 
posterior direction, as well as in thickness, resembles that of one of the lumbar vertebre. 
As far as the sixth their general direction is vertical; afterwards they have a slight but 
gradually increasing backward slope. 
Well developed rough processes, which can hardly be called articular surfaces, but 
representing the posterior zygapophyses, are formed on the hinder edge of the sides of 
the neural arch, at the root of the spine, from the first to the ninth vertebra inclusive. 
In the tenth they have almost lost their distinctive character, and they are quite obsolete 
in the eleventh. They lie above and within the prozygapophyses of the succeeding ver- 
tebra ; but, except in the case of the first two or three, they appear very rudely coadjusted, 
compared with those of ordinary Mammalia. 
The prozygapophyses are at first represented by a flattened surface on the angle 
formed by the junction of the pedicle, lamina, and transverse process of the vertebra (to 
use the familiar terms of anthropotomy), or at the root of the diapophysis. Gradually 
this part increases in prominence, and forms a distinct rounded eminence, projecting 
upwards and forwards from the side of the neural arch, and bearing the smooth 
articular surface (distinct as far as the tenth vertebra), to its inner side. The sudden 
diminution of the diapophysis on the tenth vertebra, and its disappearance on the 
eleventh (see figs. 7 and 8), leaves this, though somewhat contracted in bulk, a con- 
