( 1'7 ) 



VJI, Some Best- Attitudes of Butter flies. By G. B. Longstaff, 

 M.D., F.E.S. 



[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- 

 isra, or the turning of the body-axis so that the head 

 is away from the sun ; (2) the habit of certain Lycsenids 

 of resting head downwards ; and (3) a sideways attitude, 

 a tilting or " list " of certain Satyrids to the right or left.* 



Heliotropis'in. 



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. j* 



Mr. E. E. Green, describing the cryptic habits oi Mclanitis 

 ismene, Or., in Ceylon, says : " I have watched the fly, im- 

 mediately after pitching, alter its j)osition so that its axis 

 is directed towards the sun, thus casting no shadow." J 



Quite independently and perhaps at about the same 

 time as Mr. Green (October 1903) I saw near Simla, 

 Pararge sheihra, 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. Loud., 1905, pp. 85, 126, 135, 136. 

 t Marh Annvmrsani volume, Canibridge University, Masf. , 

 U.S.A., 1903, pp. 453-469. 



J Spolia Zeylanica, vol. ii, pt. vi, Aug. 1904, p. 76. 



TRANS. ENT, SOC. LOND. 1906. — PART I. (MAY) 7 



