EYES THAT SHINE AT NIGHT 



By Ernest P. Walker 

 Assistant Director, National Zoological Park 



[With one plate] 



The "shining" of eyes at night by the reflection of light is a com- 

 mon and generally fairly well known natural phenomenon of which 

 little has been recorded except incidentally in accounts of hunting and 

 of campfire scenes. The shining of the cat's eyes at night by reflected 

 light is probably the best known of all eye reflections. The eyes of 

 human beings very rarely shine. There are, however, occasional re- 

 ports of the shining of a human being's eyes, and I have heard of one 

 instance of a person being shot at night because his eyes shone. 

 These, however, I have not verified. 



While studying the condition and activity of small mammals in the 

 recently completed Small-Mammal House in the National Zoological 

 Park, I became interested in the different kinds of reflections obtained 

 from the eyes of different animals and proceeded to make inquiry from 

 naturalists and to search for literature on the subject. 



In A Survey of Nocturnal Vertebrates in the Kartabo Region of 

 British Guiana, Crawford l refers to the glow of eyes and lists the 

 kinkajou, jaguar, puma, ocelot, yaguaroundi, margay, opossum, three 

 species of toads of the genus Bufo, and the giant goatsucker Nyctibius. 

 He does not refer to the colors and does not mention the caimans which 

 inhabit that general region and whose eyes give perhaps the most pro- 

 nounced and beautiful glow I have observed. 



A. J. Van Rossem 2 lists 28 species of birds observed by him or 

 recorded by others as "shining." He also refers to light reflections 

 from the eyes of insects, spiders, and domestic animals. In this paper 

 he lists 3 manuscripts and 5 publications recording eye shines, and 

 brings out points that should be studied by future students of the 

 subject. No other published material on the shining of the eyes of 

 vertebrates has come to my attention. 



Examinations of the eyes of various animals as well as those of man 

 by use of the opthalmoscope have been made by several writers, nota- 

 bly Johnson 3 and Wood. 4 Both authors picture the surface of the 



» Crawford, S. C, A survey of nocturnal vertebrates in the Kartabo region of British Guiana. Journ. 

 Animal Ecol., vol. 2, p. 282, November 1933. 



i Van Rossem, A. J., Eye shine in birds, with notes on the feeding habits of some goatsuckers. The Con- 

 dor, vol. 29, pp. 25-28, January 1927. 



♦ Johnson, O. L., Contributions to the comparative anatomy of the mammalian eye, chiefly based on 

 ophthalmoscopic examination. Proc. Roy. Soc. London, ser. B, vol. 194, 1901. 



♦Wood, C A., The fundus oculi of birds, especially as viewed by the ophthalmoscope. Chicago, 1917. 



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