Four dog retinas
Date
ca.1901
Creator
A. W. Head (British) , Draughtsman
Object type
Archive reference number
Material
Dimensions
height (card support): 185mm
width (card support): 220mm
width (card support): 220mm
Subject
Content object
Description
Anatomical study of four retinas as seen through an ophthalmoscope. They belong to four eutherian mammals from the Canidae family, a cape hunting dog Lycaon pictus, racoon dog Nyctereutes procyonoides, collie dog Canis familiaris and chouchow [chow chow] Canis familiaris.
In the top two and the bottom right specimens, the fundus [internal surface] is depicted as containing three zones: a peripheral zone of either reddish brown or near black, a pale green intermediate zone and a central zone of yellow. The fundi are covered with small dots.
The bottom right specimen is divided into two zones only: a peripheral zone of near black and a yellow central zone.
The discs are round and varying in colour and the main retinal vessels tend in all directions.
George Lindsay Johnson described these specimens as follows: ‘The domestic dog, as in the case of all domestic animals, shows variations in every individual; but in no case have I found such an enormous differentiation in the colour and the appearance of the fundus as in Dogs, the difference being very much more marked than in the domestic Cats or any of the domestic Ungulates.'
Created for inclusion in George Lindsay Johnson's paper ‘Contributions to the comparative anatomy of the mammalian eye, chiefly based on ophthalmoscopic examination’ published in the Philosophical Transactions of the Royal Society B, Volume 194 (1901). However, though discussed within the paper, none are included as plates in the final publication.
The racoon dog and collie dog only appear in the posthumously published Philosophical Transactions paper 'Ophthalmoscopic studies of the eyes of mammals', as figures 21 and 22 respectively p.30-31. This paper was communicated to the Society by David Whitteridge and collates Johnson's plates in a manner not done prior to his death.
George Lindsay Johnson (1853-1943) British ophthalmologist carried out extensive research in optics, and is best known for his work on mammalian eyes. He was not a Fellow of the Royal Society.
In the top two and the bottom right specimens, the fundus [internal surface] is depicted as containing three zones: a peripheral zone of either reddish brown or near black, a pale green intermediate zone and a central zone of yellow. The fundi are covered with small dots.
The bottom right specimen is divided into two zones only: a peripheral zone of near black and a yellow central zone.
The discs are round and varying in colour and the main retinal vessels tend in all directions.
George Lindsay Johnson described these specimens as follows: ‘The domestic dog, as in the case of all domestic animals, shows variations in every individual; but in no case have I found such an enormous differentiation in the colour and the appearance of the fundus as in Dogs, the difference being very much more marked than in the domestic Cats or any of the domestic Ungulates.'
Created for inclusion in George Lindsay Johnson's paper ‘Contributions to the comparative anatomy of the mammalian eye, chiefly based on ophthalmoscopic examination’ published in the Philosophical Transactions of the Royal Society B, Volume 194 (1901). However, though discussed within the paper, none are included as plates in the final publication.
The racoon dog and collie dog only appear in the posthumously published Philosophical Transactions paper 'Ophthalmoscopic studies of the eyes of mammals', as figures 21 and 22 respectively p.30-31. This paper was communicated to the Society by David Whitteridge and collates Johnson's plates in a manner not done prior to his death.
George Lindsay Johnson (1853-1943) British ophthalmologist carried out extensive research in optics, and is best known for his work on mammalian eyes. He was not a Fellow of the Royal Society.
Related fellows
George Lindsay Johnson (1853 - 1943, British) , Ophthalmologist
Associated place