66 



FREDERICK TILNEY AND LUTHER F. WARREN 



marked paraphyseal evagination, a velum transversum, a dorsal 

 sac, a commissura habenularis, and a single thick-walled anlage of 

 the pineal body whose apex is directed cephalad. The most 

 caudal structure in the pineal region is the posterior commissure. 



Ds 



Pf 



Pig. 33 Reconstruction of a 30 mm. embryo of Thalassochelys caretta. 



Ls., lamina terminalis; Pf., paraphysis; V., velum transversum; Ds., dorsal 

 sac; Ch., commissura habenularis; Po., epiphysis; Cp., posterior commissure; R., 

 Rathke pocket. 



