Hieroglyphics of Horapollo, tr. Alexander Turner Cory, [1840], at sacred-texts.com
To denote hearing, they delineate the EAR OF THE BULL,
for when the cow is desirous of conception, (and she continues so for not longer than three hours together,) she vehemently lows, and if during this time the bull should not approach her, she reserves herself till another meeting. This however rarely happens; for the bull hears her from a great distance, and knowing that she is inflamed, he hastens to the meeting, and is the only animal that does so.