232 NERVE COMPONENTS OF BONY FISHES. 



nerves of the two sides lying close together, almost in 

 contact with each other. At this level the rami palatini 

 of the two sides pursue very similar courses, but on the 

 ventral side of the parasphenoid. Cephalad of the chiasma 

 it turns dorsad, still in the median line, and continues 

 forward close under the brain and olfactory nerves. Upon 

 the appearance of the internasal cartilage it begins to 

 diverge from the median line and soon turns ventrad to 

 enter the m. obliquus inferior. It applies itself to the 

 dorsal surface of the muscle and the coarse fibres enter 

 the belly of the muscle in many strands, while the finer 

 fibres separate and run down among the finer fibres of the 

 muscle nearer their insertion. 



The nerve for the m. rectus superior immediately after 

 its separation from the oculomotor trunk divides into a 

 dorsal portion of fine and medium fibres and a ventral 

 coarse-fibred portion, both of which turn dorsad and apply 

 themselves to the ventro-lateral face of the muscle. The 

 coarse-fibred portion at once enters the belly of the muscle ; 

 but the finer fibres follow along the smaller muscle fibres 

 of its dorsal edge, occasionally sending twigs into its sub- 

 stance, to its insertion upon the eye-ball. 



The remainder of the III nerve gives the radix breva 

 to the ciliary ganglion and at once divides into rami for the 

 mm. recti intemus and inferior. The former runs directly 

 cephalad under the m. rectus superior and over the mm. 

 recti internus and inferior. Crowded ventrally by the 

 emerging optic nerve, it crosses the cephalic face of the 

 last mentioned muscle and enters at once the m. rectus 

 internus. The coarse fibres bury themselves in its sub- 

 stance, but the finer ones run along the dorsal border or 

 embedded in a mass of exceedingly small muscle fibres 

 which occupy the dorsal part of the muscle, in which 



