The middle ear apparatus of a frog

Photomicrograph of the right middle ear apparatus of a ranid frog, seen from dorsally, caudally and slightly laterally. 1: m. opercularis; 2: operculum; 3: stapes footplate; 4: stapes shaft (pars media); 5: parotic crest; 6: ascending process of extrastapes; 7: Eustachian tube; 8: extrastapes; 9: tympanic membrane.

Close-up of the stapes footplate and otic operculum. 1: suprascapular cartilage; 2: m. opercularis; 3: m. levator scapulae superior aponeurosis; 4: operculum; 5: stapes footplate (pars interna); 6: bony stapes (pars media); 7: parotic crest; 8: ascending process of extrastapes.