HELIOTBOPISM 
549 
Ladysmith (North East Defences), August 27th. Watched 
several P. cardui, which settled frequently. They would 
settle at any angle with regard to the sun, but perhaps rather 
more often with back to it. They fanned their wings, and 
often shut them up tight (keeping them so for some time) in 
any position with regard to the sun. 
This was late in the afternoon, but I do not gather from Dr. 
Dixey (nor from personal recollection) that the sunlight was feeble, 
or that there was a strong wind, or that the butterflies were feeding 
or drinking—all disturbing causes. There can, I think, be no doubt 
that the habit of heliotropism is not as fixed in the Painted Lady 
as in many Nymphalines. 
That this butterfly, often at any rate, does orient, is clearly 
proved by subsequent experience. In Egypt, in 1909,1 saw many 
P. cardui , and find these notes:—Pyramids, January 4th, P. cardui, 
seen to orient twice. Aswan, January 23rd, P. cardui , abundant; 
many oriented. Aswan, Eebruary 25th, P. cardui , abundant; many 
specimens fresh, but chipped; several seen to orient—practically all 
those seen settled on the ground. 
Again, in the Botanical Gardens, Hobart, Tasmania, P. cardui, f. 
hershawi , McCoy, was seen to orient twice. 
Among our notes on heliotropism there are but three references 
to Pierines. The first is interesting as tending to negative the sug¬ 
gestion that the purpose of heliotropism is to mimimize the butterfly’s 
shadow and so aid in its concealment. Dr. Dixey writes:— 
Durban (The Bluff), August 16th. Teracolus ione, Godart 
( sjoeciosus, Wallgv., jobina, Butl.), <£ When first seen it was 
settled in the sunshine with wings expanded; then it flew 
a short distance and settled on a reddish sandy path. Cloud 
came over the sun, and the butterfly closed up its wings, 
so that only the hind-wing and tip of the fore-wing were 
visible. 
In explanation of this note Dr. Dixey emphasizes the fact that in 
the dry-season form of ione, the underside of the hind-wing and the 
tip of the fore-wing are reddish, hence the tightly closed attitude is 
cryptic on red soil. 1 He adds that doubtless when the butterfly 
1 The observant traveller must have been struck by the prevalence of red soils in 
tropical countries. The two following notes on the origin of red soils may be of 
interest to the entomologist:— 
Mr. R. D. Oldham, F.R.S., of the Geological Survey of India, writing of the 
Basal Carboniferous Conglomerate of Ullswater, says : “ The red colour of the fine¬ 
grained material suggests tropical or subtropical conditions, as the formation of red 
