26 MR. ST. GEORGE MIVART ON THE 
extremely long, and project inwards and postaxially in a way not to be found in Struthio 
or Rhea. The inner surface of the sternum is not so concave in either direction as in 
the last-mentioned genus. 
VERTEBRAL PARTS AND PROCESSES. 
These portions of the skeleton generally resemble those of Rhea, except in the fol- 
lowing points :— 
The centra never abort; nor do the newral lamina, as far as can be determined; but 
it is possible that they may do so in some part of the pelvis. 
The neural spines of the cervical vertebre are better-developed, but are not laterally 
bifid, though they are nearly so in some caudal vertebre. 
It is doubtful whether diapophyses are ever absent, save in the last presacral 
vertebree. 
Hyperapophyses. The interzygapophysial canals form conspicuous structures. 
The cervical styloid rids are well developed, and resemble those of Struthio and not 
those of Rhea. 
Catapophyses are developed from the sixth to the seventeenth vertebra inclusive. 
The hypapophysis is paired in the first cervico-dorsal vertebra. 
The vertebre are not raised above the acetabula. 
The vertebral ribs are stouter than in Rhea, but with the same twist. 
The wncinate processes do not seem to be ever more than two in number. 


THE AXIAL SKELETON OF CASUARIUS. 
The axial skeleton of Caswarius so much resembles that of Dromeus, that a much less 
detailed notice of the former than of the latter is alone needed. 
In Casuwarius there are fourteen, fifteen, or sixteen cervical and four or three cervico- 
dorsal vertebre; there are five dorsal and two or three dorso-lumbar vertebre; to 
these succeed nine or ten lumbar and three sacral vertebra, followed by nine, ten, or 
eleven sacro-caudal and eight or nine caudal vertebre. Thus there may be from 
fifty-five to fifty-nine vertebre in all; and of these as many as from twenty-five to 
twenty-seven belong to the first four categories, thus differing from Rhea and agreeing 
with Struthio and Dromeus. It also agrees with the last-named genus in the number 
of its caudal vertebre., 
