http://upload.wikimedia.org/wikipedia/commons/c/cb/Cochlea-crosssection.svg, http://upload.wikimedia.org/wikipedia/commons/c/c7/Cochlea-crosssection.png

A spiral-shaped cavity in the petrous portion of the temporal bone of the inner ear, containing the nerve endings essential for hearing and forming one of the divisions of the labyrinth. [TFD][VHOG]

sources vary in connection to bony labyrinth

uberon

cochlear duct, cochlear organ, cochleae, lagenas

cochlear

Because achieving high sensitivity is generally advantageous for auditory organs, it is not surprising that evidence for cochlear amplification is also seen in nonmammals. Spontaneous otoacoustic emissions (SOAEs) are narrow-band sound signals emitted from the inner ear, and it is generally assumed that their energy derives from the hair-cell molecular motors underlying cochlear amplification. However, all terrestrial vertebrates studied so far (including amphibians) show very similar SOAEs. The most parsimonious explanation for the universality of this phenomena is that some kind of amplifying mechanism is at least as old as land vertebrates themselves.[well established][VHOG]

UBERON:0001844

the cochlea is coiled in most mammals, monotremes being the exceptions., The association with 'lagena' in frog and fish comes from HOG, although HOG is inconsistent here, associating lagena with XAO cochlea and ZFA cochlear duct. NBK53175 says: 'In contrast, the ventrally located auditory chambers have undergone more extensive evolutionary modifications. The saccule and lagena are prominent auditory organs in fish but the saccule has a vestibular role in mammals and birds, and the lagena is absent in mammals. The primary au- ditory organ in mammals and birds is the cochlea, which has no known counterpart in amphibians and fish (Riley and Phillips, 2003)'

• cochlear modiolus

• vestibulocochlear nerve
• cochlear nerve

• cochlear labyrinth

• osseus cochlea