504 



EMBRYOLOGY. 



efc 



lek 



Fig. 283. Part of a section through the cochlea of an embryo Cat 9 cm. long, after BOETTCHER. 



kk, Cartilaginous capsule, in which the cochlear duct describes ascending spiral turns; dc, ductus 

 cochleares ; C, organ of Coim ; ie, lamina vestibularis ; x, outer wall of the membranous 

 ductus cochlearis with ligamentum spirale ; <ST, scala vestibuli ; ST, ST', scala tympani ; 

 g, gelatinous tissue, which still fills the scala vestibuli (.si/) in its last turns ; //, remnant of 

 the gelatinous tissue, which is not yet liquefied ; M, firm connective tissue surrounding the 

 cochlear nerve (nc) ; gsp, ganglion spirale ; N, nerve which runs to CORTI'S organ in the 

 future lamina spiralis ossea ; Y, compact connective-tissue layer, which becomes ossified and 

 shares in bounding the bony cochlear duct ; P, perichondrium. 



