Lateral Wall of the Cavum Nasi in Man. 



651 



media towards the concha suprema III we find a gradual change 

 in the plane of the conchae, from a more or less oblique direction 

 to a more or less vertical one (figs. 21 and 23). 



The ascending crura. The ascending crura always tend more 

 towards the perpendicular than do the corresponding descending 

 crura. This is especially true of the concha media and superior, 



Sipfifin /iti.si 



Concha naaa/is 

 supremu III 



Concha nasalifi 

 supremo II 



Concha itasaliH 

 suprema I 



Concha nasalis 

 superior 



Concha iiasalis 

 media 



Fig. 27 (X S) Drawino of a frontal section through 'the hiteral wall of the nasal 

 cavity in the region of the supreme conchae (fetus aged from 7-8 months, series 

 B, slide 48). The concha nasalis inferior is not included in the section. 



also at the times of the concha suprema I (figs. 21 and 24). Fig. 21 

 shows five fairly well marked ascending crura. It will be noticed 

 that they are almost perpendicular to the cribriform plate of the 

 ethmoid bone. However their superior extremities as individual 

 conchae do not closely approach this plate. We may either think 

 of the conchae as fused into one mass, or that differentiation into 

 individual conchae stopped short of the cribriform plate. The 



