550 TRANSACTIONS LIVERPOOL BIOLOGICAL SOCIETY. 
Looking into the pupil the lens can be seen. This is 
a spherical ball, built up of concentric layers of a non- 
cellular, transparent, cuticular, crystalline substance (fig. 
(8, L). Looking down into the pupil the eye appears 
black, because the dark retina shows through the lens, 
from behind. 
Sele 
Fie. V. Kye of E.cirrosa, showing various stages of dilatation of 
pupil. x 2 
The eye is enclosed in a cartilaginous cup, that 
adheres internally to the “skull.” This cup is thickest 
at the base but much thinner at its external edge, which 
reaches about half-way round the eye (fig. 85 a, orb. C.). 
iixternal to the capsule a strong muscular coat is attached 
which surrounds the eye and extends as far as the lid 
(fig. 78, Hat. Musce.). Internal to the capsule is a second 
muscular coat, which extends to the border of the pupil, 
and is more delicate than the first (fig. 78, Int. Mfusc.). 
The retina, sclerotic, &c., form a roundish, rather 
depressed chamber that only occupies about one-third of 
the whole volume of the eye. Behind this chamber is a 
second much larger one that contains the optic ganglion, 
which gives off from its external surface a great number 
of nervous strands to the retina, and the white body 
(fig. 78, Opt. G. and W. B..). 
The white body is a glandular mass surrounding the 
optic ganglion, and consists of three lobes—one large 
dorsal and two smaller ventral (Text fig. VI). This 
body has been shown to be the remains of @ 
degenerate portion of the embryonic nervous system, 
