306 



THE PINEAL ORGAN 





Ep.D. 



P.M.I). 



p. a 





- ■ 



LP.R.-iSm 



Fig 212 —Transverse Sections of Pineal Region of a 22-mm. Human Embryo 

 'and Median Aspect of the Right Half of a Model reconstructed from 



the Corresponding Series of Sections. (R. J. G.) 

 A— Section through the posterior bifurcated end of the anterior ependymal 



diverticulum in the plane A of the model. 

 B— Section through the anterior bilobed diverticulum and posterior median 



diverticulum in the plane B of the model. 

 C— Section through the posterior median diverticulum and posterior commissure 



in the plane C of the model. : 



D— Drawing of the median aspect of the right half of the model showing the 



relations of the superior and posterior commissures to the pineal diverticula. 

 A. B. C, in D indicate the planes of the sections in A, B, and C. 

 A.B.D. : anterior bilobed diverticulum. Epd. in D : epidermis. 



A.L. : epithelial buds forming rudi- 

 ment of anterior lobe. 

 Aq. C. : aqueductus cerebri. 

 Ep. D. in A : ependymal diverticulum. 



I.P.R. : infrapineal recess. 

 P.C. : posterior commissure. 

 P.M.D. : posterior median diverticulum. 

 S.C. : superior commissure. 



V. Ill : third ventricle. 



