OF THE NUBIAN GIRAFFE. 229 
the same in the transverse diameter of the base. The auricles are small as compared 
with the ventricles, which form a rounded lengthened cone. The right ventricle termi- 
nates at two inches from the apex. The left flap of the tricuspid valve has its free margin 
attached by long chord@ tendinee to the septum ventriculorum on one side, and to a co- 
lumna carnea on the other; which columna also gives attachment to some of the chorde 
tendinee of the right flap of the tricuspid ; the rest of the chorde of this flap, and all the 
chorde of the third or internal flap, are attached to a very short and thick columna which 
rises from the septum. Below the left flap of the tricuspid valve there is a fleshy column 
connecting the free wall of the right ventricle to the septum. In the right auricle 
the Eustachian valve is represented by a slight ridge circumscribing the left boundary 
of the lower cava. At the base of the heart, on one side of the origin of the aorta, and 
imbedded in the tendinous circle which gives attachment to the muscular fibres of the 
ventricle, there is a curved bone two-thirds of an inch in length. 
The arch of the aorta, after distributing the vessels to the heart itself, gives off, first, 
a large innominata which subdivides into the right vertebral artery, the right brachial ' 
artery, and the common trunk of the two carotids ; secondly, the left brachial artery; 
thirdly, the left vertebral artery. ‘The common trunk of the two carotids is remarkable 
for its length. The cranial plewus of the internal carotid is much less developed than 
in the grazing Ruminants. 
Nervous System. 
The brain of the Giraffe resembles in its general form, as well as in the number, dis- 
position, and depth of the convolutions, that of the Deer: it is more depressed than in 
the Antelope (Antilope picta) and relatively broader and deeper than in the Oz: the ce- 
rebrum lies wholly in front of the cerebellum. ‘The anterior contour of the cerebral 
hemispheres is somewhat truncated, as may be seen in the figure (Pl. XLIII. & XLIV.), 
which supersede the necessity of further description of the external form. The cerebral 
convolutions are divisible, as in other Ruminants, into primary and secondary; they 
average a breadth of three lines and are almost symmetrical in the two hemispheres. 
The two posterior convolutions next the median line, towards which they converge and 
meet in the form of a chevron, are relatively larger than in the Oz; the two larger 
primary convolutions, external to these, proceed in an undulating course from behind 
inwards and forwards, as in the Ruminants generally, but they are more complicated 
by secondary convolutions than in the Ox. There is little symmetry in the disposition 
of the primary convolutions of the cerebellum: the middle one on the upper surface repre- 
senting the superior vermiform process, pursues a wavy course from side to side ; but the 
1 The epithet “subclavian” is so obviously inappropriate as applied to the Ruminants and other non- 
claviculate Mammals, that no apology seems necessary for adopting Dr. Barclay’s term for the trunk supplying 
the pectoral extremity. 
VOL. I1.—PART III. 24H 
