Metasoa Rana. 



FlG. I79.-~HuKIZO.NTAL SECTION OF THE RIGHT EVE. (Quaill.) 



323 



, a, antero-posterior axis ; <5, b, lateral axis ; i, cornea : 2, 2'. sclerotic ; 

 3, 3', choroid; r, r 1 , retina; 4, ciliary muscle; 5, ciliary process; 6, 



10, 14, lymph canals ; 7, 7', iris; 8, 8', optic nerve; 8", point of acutest 

 vision ; 9, crinated zone marking the anterior termination of the retina ; 



11, anterior or aqueous chamber ; 12, crystalline lens ; 13, posterior or 

 \ itreous chamber. 



Y 2 



