Dimensions and orientations of the cochlea of placentalsa.

aMeasurements: Volume, total volume of cochlear canal (mm3); Coil, the total degrees completed by the cochlea; 2° Lamina, extension of secondary lamina through cochlea (°); Length, length of canal (mm); Aqueduct, length of cochlear aqueduct (mm); Ratio, aspect ratio calculated as height of spiral over width; Angle, formed between basal turn of cochlea and lateral semicircular canal (°). Values for extinct eutherians are averages [83].