190 
AMERICAN" WHITE PELICAN. 
parallel to the mandible, and about half an inch distant from it, sending off 
branches at intervals. The sac is plentifully supplied with blood-vessels. 
The nasal cavity is of an oblong form, 1 inch and 5 twelfths in length, 
passing obliquely backwards and upwards from the aperture of the posterior 
nares, and opening externally by curving forwards ; its greatest diameterS 
twelfths, in its lower third 3 twelfths, and so continuing until it expands 
into the inferior slit-like aperture, which is 8 twelfths long. The cavity of 
the nose is thus small, and the olfactory nerve, which passes out from the 
anterior part of the brain, is a slender filament, about I of a twelfth in 
diameter. It runs at first through a bony tube, then passes along the bony 
septum of the orbits, in contact for a short space with the superior maxillary 
nerve of the fifth pair, which at its commencement makes a great curve 
upwards, and crosses the 
orbit to enter the maxillary 
cavity, which has no com- 
munication with the olfac- 
tory. Fig. 2 represents the 
sternum viewed from be- 
fore. It is remarkable 
chiefly for its great breadth 
and convexity. Its sides, 
a, b, c, d, are nearly pa- 
rallel ; its posterior margin 
broad, with two shallow 
notches, e, /, separated by 
a short conical obtuse me- 
dian process. The crest or 
ridge, h, i, is carried for- 
ward in front, where it is 
only, however, of moderate 
height, and is not continued 
to the posterior extremity, 
but terminates at i, in the 
most convex part. The 
coracoid bones, i, i, are ex- 
tremely large, very broad 
at their lower part, and 
having a deep groove and 
thin elongated process, j, 
at the upper for the tendon 
of the pectoralis medius, 
