HELIOTBOPISM 
547 
Another note, also relating to Sydenham, is:— 
P. delict seen to settle, and then rapidly turn its back to the 
sun; it did not close its wings. P. delict seen here seems 
always to turn its back to the sun. 
To Dr. Dixey’s description I would add that the wings are 
usually about three-fourths expanded, nearly as with Vanessa 
atalanta , Linn., at home. One specimen was observed to settle with 
tail to the sun five consecutive times. It was only occasionally that 
I saw them close their wings over their backs, when the shadow was 
reduced to a minimum, but I did observe this several times, both in 
the neighbourhood of Durban and at the Victoria Falls. As a rule 
P. delia seemed to pitch correctly, but now and then it was seen to 
adjust itself. 
Precis cebrene, Trim., is another common and widely distributed 
South African butterfly. Though very differently coloured from 
P. delia , it is nearly, though not quite, as conspicuous when the 
upperside is displayed, but the almost uniformly clay-coloured 
underside is scarcely distinguishable against certain backgrounds, 
such as sand, clay, or rock of a grey or yellow tint. It is fond of 
frequenting dry spruits, or watercourses, settling on the rocks or 
boulders, but in the Zambesi country Dr. Dixey often saw it settle 
in trees. It was repeatedly observed to orient itself fairly accurately, 
but did not appear to close its wings as often as P. delia. A note 
made by me at Ladysmith, August 26th, says:— 
Oriented within about 10°~15°; settled often upon cliffs of 
yellow sand or mud on which it was moderately conspicuous. 
One specimen was repeatedly observed to close its wings, its 
shadow was then near the minimum and the insect -incon¬ 
spicuous. 
Precis natalica , Feld., a rather dingy species, though generally 
distributed, was much less common than the two preceding. It is 
somewhat of a shade-lover and usually settled on the ground or on 
a leaf, its wings more spread than delia or cebrene. Except when 
settled in the shade its tail was directed towards the sun. One was 
seen to close and open its wings, another was watched for some time 
and observed over and over again to orient itself correctly, and twice 
to close its wings so as to leave practically no shadow. 
Precis elgiva, Hew., is not uncommon in woods near Durban, it 
was noted as sitting with wings fully expanded and tail to the sun. 
Precis sesamus, Trim., is a dark, handsome insect, fond of hiding 
itself in ditches and under dark banks, often several together; this 
