The Vascular System 223 
At the point of union of the branches cm" and 
z° a sort of simple plexus may be formed from which 
two vessels, n, pass to the posterior nasal region, 
and two vessels pass forward along the side of the 
upper jaw. Of the latter two vessels one, which 
may be called the inferior dental of the maxilla, dm, 
is very small and extends along the maxilla to its 
very tip, at the base of the teeth and ventral to the 
palatine bone; the other, which is larger and may be 
called the superior dental of the maxilla, dm’, 
extends cephalad along the mesial side of the 
maxilla, dorsal to the palatine bone; it sends nu- 
merous twigs into the maxillary bone among the 
roots of the teeth. After passing nearly to the 
end of the snout, the superior dental, dm', suddenly 
forms a loop towards the median line and passes 
as a straight branch, n’, directly caudad, near 
and parallel to the median plane. The branch n‘* 
extends along the floor of the nasal cavity and, 
after giving off twigs to this chamber, ends in a 
network of vessels, o*, on the anterior surface of 
the eyeball and socket. 
A pair of very small arteries, n’, may be seen in 
the nasal chamber between and parallel to the 
branches, n*; they lie close to each side of the nasal 
septum and supply the anterior nasal region. 
They apparently arise, as shown by the broken 
lines, from the loop of the superior dental 
artery, dm’, though this could not be definitely 
determined. 
