Knowledge. 



With which is incorporated Hardwicke's Science Gossip, and the Illustrated Scientific News. 



A Monthly Record of Science. 



Conducted by Wilfred Mark Webb, F.L.S., and E. S. Grew, M.A. 



SEPTEMBER, 1913. 



THE EXISTENCE OF LUMINOUS BIRDS/ 



By COUNT L. de SIBOUR. 



Few students delve deeply in natural history with- 

 out encountering the topic of luminous birds, and 

 the pros and cons of the subject are developed by 

 the reader with a frequency that tests the credulity 

 of any superficial investigator. That birds having 

 the quality of luminosity have long existed seems a 

 fact beyond dispute. Especially true is this in 

 England. In 1907 Sir Digby Piggott called the 

 attention of ornithologists to the appearance of 

 luminous birds in Cambridge, and these unusual 

 members of the feathered family had already been 

 noticed by others in the same county, and especially 

 by Mr. J. H. Gurney, of Norwich, who spread the 

 news on the Continent through the French 

 ornithologist, M. Ternier, in The Ornithological 

 Review of France. 



It seems that as early as 1866, in the same county, 

 Mr. J. A. Harvie-Brown had mentioned "moving 

 lights " frequently seen at night. But no special 

 attention had been paid to these reports, as they 

 were believed to have originated in the credulous 

 minds of country folk. 



The more frequent apparitions in 1907 at last 

 aroused the attention of naturalists, especially in 

 France, where similar cases had been observed in 

 the Vosges and in the Pyrenees. 



According to Sir Digby Piggott, a couple of 

 luminous birds were seen near Twiford, Norfolk, 

 in February, 1907, by a gamekeeper, who, having 

 killed one, identified it as a common barn owl (Strix 

 Hammed). In October, 1907, Mr. B. J. Purdy and 

 Mr. Spencer saw another which was seen again on 



the 19th and 22nd of December. On the first 

 occasion it seemed to have attained the maximum 

 of luminosity, as the branches of the tree upon which 

 it had perched were visible in the pale yellow glow. 

 This light did not frighten the mice ; for the bird 

 was seen to drop upon them several times. 



The power of the light was that of a bicycle lamp 

 seen three or four hundred yards off, and its strength 

 diminished considerably when the bird's flight was 

 in a direction away from the observer. This pointed 

 to the inference that the luminosity was confined to 

 the breast. 



According to Mr. C. L. Harman, a luminous bird 

 was seen by him in the marshes of Haddiscoe, on the 

 25th day of December, 1907. Similar apparitions 

 were recorded during the years 1907 and 1908 ; but 

 in 1909 they ceased, and none has since been 

 observed. 



The glow on the breast of the barn owl is un- 

 doubtedly due to phosphorescence, and the moulting 

 of the feathers explains its sudden extinction. 



Two theories were given as to the origin of this 

 unusual luminosity. 



Mr. Gurney, who had the opportunity of observing 

 several specimens of these birds, thought it probable 

 that the owls had been in contact with phosphores- 

 cent wood, and that phosphorescent bacteria 

 had attached themselves to the feathers. This 

 opinion at first was generally accepted, especially 

 in Norfolk, where many birds had been seen, 

 and was apparently confirmed when Lord Lindley 

 announced that on his property there was a 



"Extracted from Articles by L. Ternier, in The Ornithological Review of France. 



321 



