2^0 ALUS. [Vol. XVIII. 



the place where the opticus enters it. Both the nerve and its root — 

 the radix longa — he, in their course, lateral to the rectus superior, 

 lateral to the superior division of the oculomotorius, mesial to the 

 rectus externus, dorsal to the rectus inferior, dorso-lateral to the 

 rectus internus, and dorsal to the inferior division of the oculomo- 

 torius. 



The ciliary ganghon {gc) is relatively large, and is closely ap- 

 plied to the lateral aspect of that branch of the inferior division of 

 the oculomotorius that supplies the recti inferior and internus. 

 With that branch it is connected by short fibers representing the 

 radix brevis, and many of these fibers could easily be traced a con- 

 siderable distance proximally in the oculomotorius. In the speci- 

 men used for illustration in Fig. 65 there was a smaU and wholly 

 separate ganglion lying immediately beyond the main ciliary gang- 

 lion. It was connected with the latter ganglion, and two short 

 branches arose from it, one going to the nerve that innervated the 

 rectus inferior and the other to the nerve that innervated the 

 rectus internus. This small ganglion is doubtless the homologue 

 of certain of the accessory ciliary ganglia described by Schwalbe 

 (No. 68) and Schneider (No. 67) in other animals. 



The ciharis longus {cl) runs forward and outward, or at first 

 forward and inward and then forward and outward, between the 

 rectus superior and rectus externus, and enters the eyeball in the 

 region between the surfaces of insertion of those two muscles. 

 It has the same relations to the muscles and nerves of the eyebaU 

 that the ciliaris brevis has. 



No branch was found arising either from the profundus gang- 

 Hon, or from either of the ciliary nerves, that could represent the 

 ramus ophthalmicus profundus of selachians. 



The ciliary ganglion of Scomber, with its two roots — the radix 

 longa and radix brevis — and the two ciliary nerves, were all found 

 and described by Stannius (No. 70, pp. 38-40). According to his 

 descriptions a ramus or truncus ciliaris arises directly from the 

 trigemino-facial ganglion, close to the ramus ophthalmicus, and 

 receives a sympathetic strand from the most anterior cerebral 

 ganglion of the nervus sympathicus. The truncus then separates 

 into a ramus ciliaris longus and a radix longa, the latter of which 

 enters a ciliary ganglion, from which the ciliaris brevis arises. 



