b HUMAN EMBRYOLOGY AND MORPHOLOGY. 



of Jacobson. In man the upper ends of the ducts remain open ; 

 they terminate blindly below, behind the mesial incisor teeth, in 

 the naso-palatine or incisive papilla (see Figs. 9 and 19). 



Nasal Duct. — The lachrymal sac and nasal duct, through 

 which tears pass from the eye to the inferior meatus of the nasal 

 cavity, are formed between the lateral nasal and maxillary pro- 

 cesses (Figs. 2 and 7). The epithelium of the skin (epiblast) 

 enclosed between the processes, forms at first a solid cord ; it 

 afterwards becomes caniculised to form the duct. 



Structures Formed in the Lateral Nasal Process. — In each 



mid. turb. proc. 



nasal, 

 cartil. which 

 disappears 



lateral cart. 



alar cart. ~[~ 



from mes. nas. proc. 



int. pteru. pi. 

 (pterygo-pal.bar) 



open, antrum 

 of Highmore 



(palate 

 [(pterygo-palat. bar) 



inf. turb 

 from max. proc. 



Fig. 6.— Showing the structures formed in the Lateral Nasal Processes. 



lateral nasal process a laminar plate of cartilage is developed ■ it 

 is continuous with, and forms part of, the trabeculae cranii (Fig. 

 1 3 6, p. 1 6 8). Its inner or attached margin is continuous with the 

 septal cartilage of the mesial nasal process; it forms on each side 

 the roof and lateral wall of the nasal cavities (Ficr 7) 



What becomes of the Cartilage of the "Lateral Nasal 

 Process (Fig. 6).— It forms on each side : 



(1) The cribriform plate, around the olfactory nerves as rW 

 issue from the olfactory bulb; Y 



