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VII. Some Rest-Attitudes of Butterflies. By G. B. LoNGSTAFF, 
M.D., F.ES. sb 
[Read March 7th, 1906.] 
ABOUT a year ago I called the attention of Fellows to the 
attitudes assumed by certain Indian butterflies when at 
rest, noting especially the following points: (1) Heliotrop- 
ism, or the turning of the body-axis so that the head 
is away from the sun; (2) the habit of certain Lycznids 
of resting head downwards; and (38) a sideways attitude, 
a tilting or “list” of certain Satyrids to the right or left.* 
Heliotropism. 
Professor G. H. Parker appears to have been the first to 
describe what he terms the “negative heliotropism” of 
Vanessa antiopa, L., in the United States. He records his 
numerous observations in great detail, and states that some 
species of Grapta have the same habit. The object of the 
creature thus turning its tail to the sun is, he believes, to 
display its colouring to the greatest advantage.+ 
Mr. E. E. Green, describing the cryptic habits of Melanitis 
ismene, Cr., in Ceylon, says: “I have watched the fly, im- 
mediately after pitching, alter its position so that its axis 
is directed towards the sun, thus casting no shadow.” + 
Quite independently and perhaps at about the same 
time as Mr. Green (October 1903) I saw near Simla, 
Pararge shakra, Koll., settle three times with its back to 
the sun, and noted that its shadow was thereby reduced to 
a mere line. When a butterfly with cryptically coloured 
under-side rests upon a flat surface in bright sunshine its 
shadow is often more conspicuous than the insect itself, 
so that economy of shadow may be a valuable means of 
protection. 
[The author showed specimens of South African Nym- 
phalids set in the usual manner, but close to the paper, 
and also with the wings closed as at rest, placed upon 
* Trans. Ent. Soc. Lond., 1905, pp. 85, 126, 135, 136. 
t Mark Anniversary volume, Cambridge University, Mass. 
U.S.A., 1903, pp. 453-469. 
t Spolia Zeylanica, vol. ii, pt. vi, Aug. 1904, p. 76. 
TRANS. ENT. SOC. LOND. 1906.—PART I. (MAY) 
