002 ]\rr. C. F. M. Swynueiion on 



Yellow-Hammer's egg, the white of which was oozing 

 out most temptingly as I held it to him. This egg fell 

 accidentally at his fore feet where he was lying, and he 

 stooped, tasted, and refused it, began to lick up the contents 

 of a Dove^s egg in which the yolk had become mixed with 

 the white, refused (first smelling it) the other Dove's egg 

 in which these were separate, and returned to his eating of 

 the first. He then repeated all his previous refusals, but 

 readily attacked a Greenfinch's egg and, on my withdrawing 

 it, followed it out of his sleeping-box — a thing he had done 

 to no other egg in this experiment ; again repeated his 

 refusals, including fowl, but was rather inclined to eat the 

 fowl's egg in which yolk and white were mixed. 



That he was still not replete was shown by his eating 

 half a not irreproachable Guillemot's egg. The few offerings 

 that closed the experiment once more included eggs that 

 were not fresh, so that they are again hardly worth detailing. 

 A Greenfinch's egg was attacked when the Guillemot's, 

 mixed Dove's and other eggs were being refused. A fowl's 

 head was also refused, but beef would certainly have been 

 eaten. 



Order of preference : (1) Greenfinch. (2) Fowl and Dove, 

 in which yolk was mixed with white. (3) Meadow-Pipit. 

 (4) Duck, Turtle-Dove, Grey Wagtail, Pied Wagtail, Wren. 

 Yellow-Hammer comes in (3), (4), or (5). (5) Fowl, 

 unmixed. (G) Fowl's intestines, placed below Fowl's egg 

 on previous night and other occasions. 



Apart from the preferences, three points were interesting. 

 These were (1) the mongoose's greater dislike for the white, 

 seeming to show that the albumen is rather specially the 

 carrier of the egg's defence ; (2) his readiness to eat stale 

 eggs — he even showed preferences as between species that 

 were apparently equally stale; and, (3), a possible special 

 repugnance to fowls' eggs as a I'esult of having had to feed 

 on them alone on the previous night. I have seen a similar 

 repugnance in insectivorous birds towards an insect of 

 which they had just been given too exclusive a supply. 



