endolymph 



vestib. 

 pouch " 



qroove 



c.sc.post., absorpt.foci 



I at groove 



"f. 307. lateral. 



FIG. 385. Six stages in the development of the internal ear (Streeter). X 25. The 

 figures show lateral views of models of the left membranous labyrinth a at 6.6 mm. ; b, at 9 

 mm. ; c at 1 1 mm. ; d at 13 mm. ; e at 20 mm. ; and / at 3o'mm. The colors yellow and red are 

 used to indicate respectively the cochlear and vestibular divisions of the acoustic nerve and its 

 ganglia, absorp. focus, Area of wall where absorption is complete; crus, crus commune; c.sc.lat., 

 ductus semicircularis lateralis; c.sc.post., ductus semicircularis posterior; c.sc.sup., ductus semi- 

 circularis superior or anterior: cochlea, ductus cochlearis; each, pouch, cochlear anlage; endolymph., 

 appendix endolymphaticus; sacc., sacculus; sac. endol., saocus endolymphaticus; sinus ut. lat., 

 sinus utriculi lateralis; utric., utriculus. 



