part_of part of part of middle ear auditory ossicle cartilage element stapes columella XAO:0004310 2012-03-10T10:07:32Z Bone of the ear that is connected to the tympanic membrane via the extrastapes. This structure is the amphibian ear ossicle, also known as the columella. It extends between extrastapes cartilage and the oval window. The extrastapes forms a cartilaginous tympanic disk. eriksegerdell xenopus_anatomy