Optomotor responses by echolocating bats.

Optomotor responses to moving stripes have been elicited from nine species of Microchiroptera. The minimum separable visual angle of two phyllostomids, under the experimental conditions, probably lies between 3.0 and 0.7 degrees; that of Myotis lucifugus, between 6.0 and 3.0 degrees. Four species indicate an ability to resolve stripes subtending 0.7 degree, the narrowest tested.