CRANIAL NERVES OF SIREN LACERTINA Die 
thalmicus profundus (op.); dorsally a group of fibers (Vad.V IJ) 
separates to join the dorsal lateral line division of the facial 
nerve. 
3. The ramus mandibularis V 
This nerve of motor and general cutaneous fibers passes out 
through a foramen, common to it and the dorsal lateral line divi- 
sion of the seventh nerve, between the orbito-sphenoid cartilage 
and the postorbital process of the petrosal cartilage (figs. 10, 11, 
md.). ‘These nerves emerge where the orbito-sphenoid cartilage 
becomes distinct from the petrosal and the latter is separate from 
the quadrate cartilage. Figure 10 shows the lateral line trunk 
passing dorsally out of the interval between the orbito-sphenoid 
and the petrosal, and the ramus mandibularis turning laterally 
around the ventral border of the latter. The ramus mandibularis V 
passes out of the cranium on the dorsal border of that portion of 
' the temporal muscle which has its origin on the orbito-sphenoid 
cartilage and bone (figs. 10, 11, émv.). Farther anteriorly and 
laterally it has a position between the temporal and masseter 
muscles, and farther on passes through the masseter. As it is 
passing out through the interval between the petrosal and the 
quadrate it gives off a few minute twigs to the temporal muscle. 
The first branch of considerable size (fig. 44, md.1) is given off 
from the ventro-medial border and supplies the temporal and 
pterygoid muscles and also sends a small branch (mao.) to two 
small muscles connected with the antorbital cartilage. A second 
branch (md.2), which is sometimes the first given off, supplies the 
masseter muscle and sends posteriorly a large general cutaneous 
branch, ramulus malaris, to the skin overlying the region of the 
angle of the jaw. A third branch, in figure 44 included in the 
preceding, passes dorsally between the temporal and masseter 
muscles and supplies the latter. The main nerve passes antero- 
ventrally through the masseter muscle to the dorso-lateral border 
of the lower jaw, where it divides. (a) One branch (md.4), of 
motor and general cutaneous fibers, the ramulus intermandibu- 
laris, enters the jaw between Meckel’s cartilage and the dentary 
