Effect of Alcohol and Anesthetics on Development. 381 
: 15 
Fig. 15. A diagram illustrating several positions taken by the optic. cups in 
development. A, the usual case in which both cups push out trom the brain and 
turn dorsally so as to face the lateral head wall with their convex choroid surfaces 
towards the brain; see fig. 12. B, the optic cups push out from the brain but in- 
stead of growing Morealie: they fang ventrally and face in towards the median 
plane, - with their convex choroid surfaces against the outer head wall; see figs, 13 
and 14. Cand D, the same conditions are often realized when only one optic ves- 
icle arises from the brain. 
