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TABLE XXXllI. 



Systematic Survey of the Development of the Human Ear. 



I. Survey of the parts of the Internal Ear. (Apparatus perceptive of sound.) 



1. Stalk of the primary l. Aqueduct of the Aquceductus vestibuli 

 ear-vesicle vestibule {Due- s. Hecessus labyrinthi 



tiis endolym- 

 phaticus) 



Products of the < 

 Horn-plate 



B. 

 Products of the 



Head-plate 



2, 3. Upper part of the 2. Ear-pouch ULriculus 



primary ear-vesicle 3. Three semi-circu- Canales semi-drcu- 



lar, or curved 

 canals 



4, 5. Lower part of the 4. Ear-sac 



primary ear-vesicle 5. "The snail" 



Sacculus 

 Cochlea 



G. Auditory nerve 6. Auditory nerve JVervus acusticzis 



1. Bony covering of the T. Osseous labyrinth Labyrinthus osseus 

 membranous laby- 

 rinth 



8. Bony covering of the 8. " The stony bone " 

 V whole internal ear 



s petrosum 



II. Survey of the parts of the Intermediate and External Ear. (Apparatus for the 

 conveyance of sound.) 



Products of the 



first 



Gill-Opening 



D. 



Products of the 



first two 



Gill-arches 



I 9. Inner part of the first 9. Eustachian tube TiCba Eustachii 

 gill-opening 



10. Central pirt of the first 10. Tympanic cavity Cavum tympani 



gill-opening (Interior of the 



drum) 



11. Closed part of the first 11. Tympanic mem- Memhrana tympani 



gill-opening brane (Head of 



the drum) 



12. Upper part of the 12. Stin-up {First Stapes 



second gill-arch bonelet of the 



ear) 



13. Upper part of the first 13. Anvil (Second Incus 



gUl-arch bonelet of the 



ear) 



14. Central part of the first U. Hammer (Third Malleus 



gill-arch bonelet of the 



ear) 



Product of the 

 Head-plate 



Product of the 

 Skin-covering 



15. Tympanic circle 15. Bony outer audi- Meatus auditoHus 



(^Annulus tympanicus) tory passage osseus 



Concha auris 



/le. Circular membranou.g 16, Ear-shell 



fold at the closed part 

 J of the first gill- 



) opening 



IV. Rudimentary ear- MuscuU conchce, 

 V mtiscles 



