TKxr-FiG. 2.— Camera tracings of sagittal' scctionti through the brain of Lcpidohircn 

 at successive periods of development. Figs. A— G are drawn under the same magnifica- 

 tion, Fig. H under a lower magnification. A stage 25, B stage 28, C stage 29 x, d stage 

 31, E stage :il X , f stage '-io, G stage .'18, h adult in second year. 



Itefrmicr Lrltcrx : a. Anterior end of tlmn' of brain rudiment, a.c. Anterior commis- 

 sure, c.h. Cerebral hemisphere, ch. Optic chiasma. r/i. Pineal body, i/.liab. Ganglion 

 habenulw. A. f. nabcimlar (superior) commissure. Ii;/)i. Hyi)ophysis cerebri, /mr. Tara- 

 physis. p.c. Posterior commissure, pi, lat. Uhoroiil plexus of lateral ventricle. j>.r. 

 Saccus vaticulosus. vel. Plexus of third ventricle. 



Structures occurring not in the sagittal plane, but in sections parallel to but some 

 distance from it, are shaded with (ihli(|un lines. 



