332 MR. W. K. PARKER ON THE OSTEOLOGY OF BALANICEPS REX. 
extent, the rest are rather shorter, and are about the same length as the spine of the last 
cervical. These spines gradually increase in height, the first being one-fourth, and the 
last half an inch high. The upper ridge of the spine is the longest part ; it is bifurcate 
behind and sometimes in front. The spines are thickest below, and thicker at their 
posterior than at their anterior margin. Their shape is oblong, the last being nearly 
square, but pitched, as it were, obliquely forwards. The anterior and posterior edges 
are rough for the attachment of the elastic ligament. The dorsal vertebre are 13 inch 
wide across the strong thick diapophyses (Pl. LXVI. fig. 7), the last being the widest by 
a line or two; the diapophyses are widest in the first and narrowest in the last dorsal. 
These latter processes rise a little as they pass out from the neural arch ; they are concave 
in outline in front and very arcuate behind, the terminal third being extended in the an- 
tero-posterior direction, and is on an average more than half an inch broad at this part. 
The terminal part of the diapophysis is bevelled downwards, becomes narrow again, 
and just beneath its tip forms the flat oblique articular surface for the ‘ tubercle’ of the 
rib. The diapophyses are very broad where they are one with the neural arch, and at 
this part in front each diapophysis has two or three large pneumatic foramina, and there 
is another large one on each side higher up at the junction of the diapophysis with the 
neural spine. The large oblique zygapophyses are much like those in the lower cervicals, 
but they gradually become smaller and nearer together as we pass backwards. Beneath 
each pre- and post-zygapophysis there is a large rounded, smooth, crescentic notch, 
which is formed into a foramen by the corresponding notch in the contiguous vertebra ; 
this foramen is for the exit of the spinal nerves. These round notches have much the 
same character from the axis to the pelvis ; they are formed at the expense of the strong 
vertical neurapophyses, which elements dilate above into the zygapophyses, and below 
into the expanded part which becomes confluent with the centrum. A large space, 
between the zygapophyses, of the spinal canal is left unprotected by bone. The arch 
formed by the confluent neurapophyses has a large crescentic notch both before and 
behind in the upper cervical vertebree and in the dorsals, being smallest in the dorsal 
region, But in many of the middle cervicals the emargination between the post-zyga- 
pophyses is very large and triangular. These upper inter-laminar spaces are filled up 
in the fresh state by strong interosseous membrane. The spinal canal, very wide in the 
lower cervical region, becomes narrower in the dorsal, expands very much in the middle 
part of the sacrum, to narrow more and more down to the last caudal. The ribs are 
relatively inferior in strength to those of the more robust, thick-bodied Adjutant ; the 
second dorsal rib is strongest and has a medium width of a quarter of aninch. Only the 
four true dorsal ribs have appendages (Pl. LXVI. fig. 1 ap), the longest of which on the 
second rib is less than an inch in length. The cupped short parapophyses that receive 
the rounded head of each rib rise higher, as we pass backwards ; those of the last two 
dorsals being at the upper margin of the centrums. 
The bodies (centrums) of the dorsals are more like those of the Storks than those of 
