A further investigation of the development of hearing in the opossum.

Abstract

In a litter of pouch-young opossums of the sp. Didelphys virginiana the course of development of cochlear responses was followed from a primitive stage at 48 days after birth to an essentially adult condition at 77 days. The range of tones to which responses occur, and the degree of sensitivity to these tones, present a pattern of development similar to that already demonstrated for the related Didelphys marsupialis. A prominent feature of this development is the long-continued growth of sensitivity to high tones.