582 Mr. C. F. M. Swynnerton on 



M. a-oceus (yesterday^s clutch), but I withdrew it ; ate a 

 C. semitorques egg (blotched) left uneaten from yesterday 

 and the remains of the Hyphantornis and A. albifrons eggs 

 of yesterday (a good deal less than half in each) ; ate the 

 whole of the remainder of the Macronyx egg and the rest of 

 the Dove's, then another A. albifrons and neglected the 

 next, as also one of H.jamesoni (spotted blue) and one of 

 C. ardens. Later he had eaten part of the latter and was 

 now neglecting it, and he also neglected an egg of C. ardens. 

 He similarly neglected, as persistently, the eggs of P. rnystacea, 

 Cisticola semitorques (practically spotless, pale blue, unusual), 

 C. afrtty and M. croceus. He became irritable at the end, 

 and knocked the last two eggs right away with his fore feet, 

 and kept gnawing savagely at the ground. Whether these 

 symptoms of irritation were provoked by my insistence, by 

 dislike of the eggs oflFered, or by internal happenings, I 

 was unable to judge. He also refused to touch bread, 

 either in scraps or in large pieces, even when placed in his 

 cage. 



The sun now began to break through the clouds, and as 

 it had been very cold in the verandah I put him out. He 

 soon began to show much liveliness, and attacked and 

 finished the bread — two or three of the pieces being fairly 

 large. 



This lapse into apparent indiscriminativeness was puzzling. 

 I have seen the same thing happen in the case of a Butcher- 

 bird (Lanius coliaris), normally discriminating, in relation 

 to highly nauseous insects. It may conceivably have been 

 due to a lack of the animal element in the rat^s diet during 

 the last twenty-four hours (except for last night's C. ardens 

 egg), or, very likely, it may not. 



Expt. 7. Feb. 5. — I left in a hard-set Macronyx e^^ from 

 the first clutch. The rat ignored it for a long time. I 

 added an egg of A. albifrons and went away. On my return 

 fifteen minutes later both eggs remained untouched. I 

 added an egg of 8. ocularia (typical coloration), and, being 

 still busy, left for twenty minutes. On my return I found 

 the last-named egg licked clean out, and the other two still 



