EYE OF THE ENGLISH SPARROW 389 



The ciliaay ganglion {eg, figs. 21, 22, and 24, c) is situated 

 directly on a branch of the third nerve. This branch may be 

 given off at the point of division of this nerve into the superior 

 and inferior branches as seen in figure 21, or it may leave the 

 superior branch of the third as far from the main division as 

 shown in figure 22. The branch connecting the ganglion with 

 the third nerve is very short. In fact, the position of the gan- 

 glion could almost be described as located on the side of the 

 nerve. From the distal side of the ganglion I have found in all 

 cases at least tw^o branches and sometimes three. When but 

 two branches occur, one of these divides very soon into a small 

 and a large branch, varying in the location at which the small 

 branch is given off. These two nerves run %o the dorsal side of 

 the optic nerve. The smaller branch divides into three parts 

 which immediately pierce the sclera in three places in the angle' 

 formed by the optic sheath and the sclera. The larger branch 

 extends a little farther forward. It divides into four fine branches 

 which pierce the sclera at four distinct points in this same angle 

 {sc, figs. 21 and 22). These little branches form seven of the 

 short ciliary nerves. 



The other large branch which leaves the ciliary ganglion is 

 directed downward along the posterior side of the optic nerve. 

 It is joined about midway of its course by the small branch from 

 the ophthalmic nerve. This common trunk extends on down- 

 ward to where the long ciliary artery pierces the sclera. Here it 

 divides into a large and a small branch which immediately pene- 

 trates the sclera at two places. 



When the sclera is removed, the distribution of these nerves 

 over the chorioid is readily seen (figs. 25 and 26). The seven 

 short ciliary nerves, referred to above, radiate in practically all 

 directions from the place of entrance. The distribution of the 

 nerve formed by the union of the branches from the third and 

 fifth nerves is as follows: The smaller branch, visible on the out- 

 side of the eye, is a short ciliary nerve. The larger branch 

 divides at once after reaching the chorioid into the two long 

 ciliary nerves which lie on the surface of the chorioid and extend 

 around the lateral side to the ciliary region (fig. 26). Here they 



