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optic nerve, is elongated in the longitudinal axis of the 
body, and curves round the nerve so that its concave 
margin faces the temporal side of the eye. It is not a 
gland sensu stricto, but a rete mirabile. The ophthalmic 
artery on entering the bulb immediately breaks up into a 
number of short capillaries which run transversely to the 
long axis of the gland; at the lateral margin these turn 
backwards on themselves, and open into a very prominent 
vein which traverses the whole length of the gland. From 
this vein a very short transverse trunk pierces the sclerotic 
and forms outside the bulb the distal extremity of the 
superior jugular vein. We are unaware of any plausible 
hypothesis as to the function of this organ. 
The Retina presents no features of special interest. 
The radiation outwards of the fibres of the optic nerve 
towards its periphery is very striking. A prominent black 
line runs outwards from the place of entrance of the optic 
nerve to the temporal margin of the retina. This is the 
choroidal fissure, which here divides the retina, and by 
exposing the pigmented choroid beneath shews as a black 
line. 
The Processus Falciformis and Campanula Halleri. — 
A delicate fold of the choroid projects through the 
choroidal fissure into the vitreous humour. ‘This is the 
processus falciformis. Its distal extremity is swollen out 
into a bilobed pear-shaped enlargement—the Campanula 
Halleri, which is attached to the lens. These structures 
are said to form an accommodation apparatus. Accom- 
modation in the fish eye is effected not by an alteration in 
the curvature of the lens but by its approximation to the 
retina through the contraction of the muscular tissue in 
the above campanula and processus. ‘The elasticity of the 
suspensory ligament increases the distance between lens 
and retina. 
