220 THE FIFTH PAIR OF SERVES. 



frontal orbital process, where it anastomoses with the 

 sapra-orbital and with ramifications from the superior 

 maxillary. It is also lost on the integument and 

 muscles of the forehead. The lateral nasal is the 

 largest of the three. Almost at its beginning we ob- 

 serve the filaments that help to form the Ophtlialmic 

 Ganglion. They ar3 more numerous and more easily 

 traced in some of our domesticated animals than in 

 others, and the ganglion itself is difibrently developed, 

 but for what physiological purpose I know not. It is 

 comparatively larger in the ox than in the horse, and 

 sends more filaments to the iris. Four distinct fila- 

 ments may be traced in the ox, but seldom more 

 than two in the horse or the dog. To these fila- 

 ments others of the ophthalmic, that have not passed 

 through the ganglion, afterward join themselves; so 

 that the ciliary are also minute compound nerves of 

 motion and sensation.* 



* " The best account, liowev^er, of this is ^ven by Dr. Jonas 

 Quain (' Qnain's Anatomy/ p. 7(>8). He considers the ganglion 

 as a center of nervous influence — a little brain, as it were — and 

 the filaments which some anatomists describe as composing, he 

 speaks of as branches given out from it. ' It lies,' says he, 

 ' within the orbit, about midway between the optic foramen and 

 the globe of the eye, and is inclosed between the external rectus 

 muscle and the optic nerve. It is exceedingly .small and, owing 

 to its being imbedded in the soft adipose tissue which fills the 

 interstices of the different parts within the orbit, difficult to find. 

 Its branches are the following: From its anterior border from 

 sixteen to twenty filaments issue, which proceed forward to the 

 surface of the sclerotic, and pierce it through minute foramina. 

 These arc the ciliary nerves. In their course to the globe of the 

 eye they are joined by one or two filaments derived from the 

 nasal nerve, but they do not form a plexus (an interlacement). 

 They become, however, dispersed or divided into two fasciculi, 

 one above and the other below the optic nerve, the latter being 



