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some small lightly staining fibres. These are for the most 
part handed over to the lower nerve, and collect at its 
outer side. Finally they pass over into the ciliary 
ganglion and hence form the radix brevis (fig. 26, rv. 6.) 
of that ganglion. 
The upper division of the oculomotor (7.s.) passes into 
the Rectus superior muscle of the eye. Its small fibres 
are distributed to the smaller fibres of its muscle. 
The lower division soon after leaving the ciliary 
ganglion, to which it has been closely opposed, passes 
sharply downwards and forwards accompanied at first by 
the ramus ciliaris brevis from the ciliary ganglion (fig. 26, 
cil. b.). It splits into three almost equal branches, which 
soon take up the following positions in the vertical plane, 
and are as below: — 
(a) Dorsal branch (r. zt.). To rectus internus. Passes 
upwards and inwards and reaches the ventral surface of 
the lower or right optic nerve. It subsequently breaks up 
in its muscle between and below the two optic nerves. 
(0) Intermediate branch (7. zf.). To rectus inferior. 
Divides into three principal twigs which enter their 
muscle in the order shown in the figure. 
(c) Ventral branch (02.). To obliquus inferior. 
Descends and crosses the palatinus vii. internally and for 
some distance les just below and internal to it. It then 
rises, crosses the palatine again, and now lies to the inner 
side of the rectus inferior. From this point it courses 
almost straight forwards at the right side of the 
parasphenoid and ethmoid cartilage, and finally splits up 
to enter its muscle in the way shown in the figure. 
As regards now the left side, it may be noted at once 
that the distribution of the eye muscle nerves, except 
those coursing far forwards like the patheticus and the 
branch of the third to the inferior oblique, is not much 
