106 Dr. G. B. Longstaff o?i 



given by the light or warmth of the sun's rays, I am 

 unable to determine, but that in the case of such species 

 as Pararge mcgxra and Precis clclia the diminution of 

 the shadow when the wings are closed helps to conceal 

 the butterflies from their enemies I have no longer any 

 doubt.* 



Further observations will show how far the habit is 

 general within the families in which it has been observed, 

 and whether it prevails in other families. 



The inverted attitude of Lyexnids. 



In the paper first referred to I drew the attention of the 

 Society to the fact that the curious lobes at the anal angle 

 of the hind-wings of certain Indian Lyca^nids, to wit species 

 of the genera Aiihiwiis, Prata'pa and RajKda, are everted 

 so as to be nearly at right angles to the plane of the wing. 

 I showed by a diagram that this eversion of the lobe 

 helped in the suggestion of a head where the tail should 

 be. The original sketch for the diagram was made before 

 I had heard of the "false head theory." f The resemblance 

 would of course be more striking if the Lycsenids in 

 question, like so many of the family, habitually rest with 

 the head downwards. 



Prof. Poulton discussed the " false head " at some length 

 in his notes to Mr. G. A. K. Marshall's paper on "The 

 Bionomics of South African Insects.":}: Prof. Poulton showed 

 b}' a reference to Kirby and Spence that the resemblance 

 of the tails of some Lycaenids to antenna3 was observed 

 early in the 19 th century. I venture to give the passage 

 in full : — 



Dr. Arnold has made a curious observation (confirmed 

 by Dr. Forstrom with respect to others of the 

 genus) on the use of the long processes or tails that 

 distinguish the secondary wings of Hesperia iarhas. 

 These processes, he remarks, resemble antennjE, 

 and when the butterfly is sitting it keeps them in 

 constant motion ; so that at first sight it appears to 



* In the discussion which followed the reading of the paper the 

 President (Mr. F. Merrifield) threw out the suggestion that possibly 

 the object of negative heliotropism might be to enable the butterily 

 to see to the greatest advantage. 



t Trans. Ent. Soc. Lond,,l905, pp. 85, 86. 



X Trans. Ent. Soc. Lend., 1902, pp. 373-375. 



