542 
BIONOMIC NOTES 
In the discussion which followed, Mr. C. 0. Waterhouse suggested 
a third possible explanation of this habit, viz. that this special 
attitude exposed not only the wings, but the insect’s body, most 
completely to the sun’s rays. Doubtless we may fairly suppose that 
such an essentially sun-loving creature as a butterfly finds them 
agreeable. 
I studied the matter further both in Devonshire and South Africa, 
and here quote the relevant passages of a paper on Some Rest- 
Attitudes of Butterflies ; 1 merely adding by way of explanation that 
I have found it convenient to make use of the word Orientation and 
to speak of a butterfly with its tail pointed accurately towards the 
sun as correctly oriented. 
After somewhat intimate acquaintance with P.meone, in Algeria, 
it was pleasant, in May, 1905, to study its Northern form, P. aegeria , 
which is common in and about my garden at Mortehoe, North Devon, 
and this was the more pleasant because our butterfly is undeniably 
more beautiful than its Southern sister. 
I have notes on ten specimens observed, and it may be instructive 
to give them in detail. 
May 3. Observed two P. aegeria ; one settled several times with 
tail to the sun, the other was less particular. 
May 9. Saw aegeria settled with wings open and tail directed 
towards the sun. 
May 15. Saw one specimen of aegeria settle twice with fairly 
accurate orientation ; another specimen settled first accurately 
oriented; then it settled again with the body nearly at right 
angles to, but with the head somewhat towards, the sun ; thirdly, 
it settled again at right angles, but with its head turned to the 
opposite side. 
May 19. Watched three specimens of aegeria and saw each of 
them orient itself accurately twice. The same day I saw 
another specimen orient itself four times. 
My last observation was made on an aegeria within a few yards 
of my study window; this I disturbed many times with a view to 
noting its behaviour; out of seventeen occasions it oriented itself 
correctly but five times, it faced the sun once, but placed itself at 
right angles to its rays no less than eleven times. 
The unusual behaviour of this butterfly gives strong proof that 
individual flies may differ much in behaviour, and as I should be 
disposed to describe it, in moral character. What entomologist who 
1 Trans. Ent. Soc. Lond ., 1906, pp. 97-106. 
