134 EMBRYOLOGY OF THE LOWER VERTEBRATES MI 

 invaginated to form a cup-like structure the optic cup (Fig. 74, 

 thai 



pi 



ect 



\\m\\\\\\ 



A. 



lhal. 



limliiiil 



liiiilinil 



n|' Kn\vl t-mliryos. 



..jiiiH-m .r iii,. eye as MTU in 



A, latter half Of *<-<Mii il.-iy n\ incubul i.,n KOOBd 'l.-.v . ' ' l:itt-r 



liAlfofl.- ' 'XlMii;il ci-to-lfini ; /. l.-n.s ; ... , , i ii.liiiifiit of ye ; o.s, optii- htulU ; /../. i 



layer of Mtiiift ; /', r-tin;i ; llml, wall ( tli:il;iii:.-iic.-|.|i:,|.,n. 



I', and C ; . 



cuj.-likc Inis-nuliini-iit !(. ,incs ^radtiallv con- 



