RUDIMENTARY EYES 



727 



Figs. 870 and 871. — The Eye of Photeus axguisus. 



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Fig. 870. — A vertical section through a rudimentary lateral eye in an animal of 

 normal cavernicolous habit. The eye is seen to be a sim]3le vesicle containing 

 vitreous-like material centrally. It is surrounded by jsigmentary eijithelium and, 

 owing to the absence of the lens, the lips of the optic cup meet at the distal 

 aspect of the vesicle. The retina is unusually thick and relativelj' undifferenti- 

 ated. The entire organ lies underneath the skin (E. F. Finchani). 



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Fig. 871. — Mciidional section through the eye of an animal kept in daylight. Note 



the presence of the ill-formed cornea, the well-formed lens and uveal tract, 



the hyaloid type of vascularization and the highly differentiated retina (after 

 Kammerer). 



