EXPERIMENTAL ANALYSIS OF THE VISUAL SYSTEM OF THE FOUR-EYED FISH ANABLEPS MICROLEPIS,
Abstract
Specialization of optical structures in the Anableps eye allows simultaneous vision in air and water in two different optical axes. The tectal projection of the aerial and aquatic visual field was mapped by electrophysiological methods and was found to be similar to that in freshwater fishes, except for an area above the waterline with greatly enlarged tectal magnification in Anableps, correlated with increased ganglion cell density in the corresponding retinal region. Size threshold for movement perception is lower in the aerial visual field than in the aquatic field and seems correlated with higher cone density in the ventral retina. Finger-like iris flaps between the two pupillary apertures prevent double-image formation due to light refraction at the waterline. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 15, 1965
- Accession Number
- AD0619235
Entities
People
- Horst O. Schwassmann
- Lawrence Kruger
Organizations
- University of California, Los Angeles