Dissection oj Sheeph Head. 245 



At this point the Third nerve will be found to send off a 

 branch tending to the inner aspect of the orbit, to supply the 

 inferior rectus muscle ; the main stem continuing rather 

 towards the outer side of the eyeball. 



It will next be well to gently separate the suspensorius 

 from the external rectus : these two muscles will be found 

 intimately united at their origin ; and more, they are both 

 supplied by filaments from the same nerve, viz.y the Sixth. 



Dissection of Lenticular or Ciliary Ganglion. 

 We previously directed attention to the line of demarca- 

 tion between the superior and external recti muscles : it 

 will now be well to separate their apposed edges in the same 

 way that the others have been treated: only in this case 

 with more care, for, within their lips, where the two difierent 

 nerves seem to converge, will be found the Lenticular or Ciliary 

 ganglion, a knot of nervous matter, not very readily distin- 

 guished from the surrounding fat, except by its slightly 

 reddish tint. In situation it may be described as occupying 

 the centre of a triangular cavity enclosed by the Optic nerve, 

 and the external rectus, and suspensorius muscles. By its 

 inferior border, the ganglion will be seen to have branches 

 of communication with other nerves ; and in the ganglion 

 sensory, motor, and sympathetic filaments are combined. A 

 short thick branch passes from its lower margin to join the 

 branch of the Third nerve, which is now seen to continue 

 forwards towards the anterior external boundary of the orbit ; 

 and a second branch, or rather main factor, comes from the 

 Fifth ; it is also connected with the sympathetic system by a 

 nerve emanating from the cavernous plexus of the Sympathe- 

 tic. From the superior border of the ganglion proceed two 

 branches, each of which consists of a bundle of small twigs ; 

 these extend along the Optic nerve to the eyeball, which they 

 enter by apertures in the back of the sclerotic coat ; and are 



