MEDIAN AND VERTICAL SECTION CF A THREE 

 MONTHS' EMBRYO, [Ue]erine,] 



1, .aqueduct of Sylvius. 2, Medulla Dblongata. 3, Central 

 Canal, 4, Infundibulum and Pituitary Ha dies [the latter have 

 been added to the original], 5, Optic Thalamus, B, Fourth 

 Ventricle, 



