Organ of Hearing. 



229 



The external au- 

 ditory canal consists 

 of a cartilaginous 

 portion, Meatus audi- 

 torius cartilagineus, which 

 is a prolongation of the 

 cartilage of the ear, and 

 through which several 

 shallow fissures, Incisu- 

 rae Santorinianae, extend 

 transversely; and of a 

 bony portion, Meatus 

 auditorius osseus, which 

 is part of the temporal 

 bone. At the inner end 

 of the latter is a groove 

 for the insertion of the 

 Membrana tympani, Sul- 

 cuspro membranatympani. 

 The skin of the exter- 

 nal meatus is continuous 

 with that covering the 

 pinna, and possesses fine 

 hairs - - Hirci ; in the 

 thick subcutaneous tissue 

 of the cartilaginous por- 

 tion of the meatus are 

 small oval glands, similar 

 to the sweat glands, 



Glandulae ceruminales, 

 which secrete the ear 

 w a x, Cerumen. 



Incus 



Canalts Fallopiae 



egtra. ovalis 

 Umbo 



romantovtum, 

 -Mevn.br. tympani 



.vutn tympani 

 tens.tip p . 

 Sulc-pr. membr. tymp. 



is.Santorin. 



310. The External Auditory 

 Ganal and the Tympanic 



Cavity in section. 



Jnctsurae 

 Santorini 



311, The Incisurae Santorini of the 

 Cartilaginous Auditory Canal. 



