168 



HUMAN EMBRYOLOGY AND MORPHOLOGY. 



(3) Trabeculae Cranii (Figs. 135 and 136). — The notochord 

 terminates behind the pituitary body and sella Turicae ; the para- 

 chordal cartilages develop above and at each side of it (Fig. 135). 

 Two bars of cartilage — the trabeculae cranii — develop in the 



trabecula. 



cornu 



trabecula 



1_ pituitary 



periotio 

 ^■^Apetro-mast. ) 



parach. cart. 



notoch. 



Fin. 135. — Diagram of the Trabeculae Cranii, Parachordal Cartilages, and Periotio 



Capsules. 



septum of nose 



lat. nas. cart. 



lat. mass, ethmoid 



cribriform pi. 

 r small wing 

 isphen. 



optic, for. 



pituitary 



trabecula 



Periotio 

 (petro-mast) 



great wing 

 sphen. 



petro-mast. 



-parach. cartil. 



Fig. 136.— Diagram of the structures formed from the Trabeculae Cranii. 



membranous basis of the embryonic brain capsule in front of the 

 notochord and on each side of the pituitary body. In Fig. 136 is 

 shown what become of these two cartilaginous bars. Their posterior 



