In the eyes of the guinea pig about the same proportion of hypermetropia existed.
"Scientific American Supplement No. 822" by Various
DONDERS, Dr., hereditary hypermetropia, ii.
"The Variation of Animals and Plants Under Domestication, Volume II (of 2)" by Charles Darwin
Among them 3 with double hypermetropia, 2 with emmetropia in one, and hypermetropia in the other eye.
"Schweigger on Squint" by C. Schweigger