Resting attitudes in some Lepidoptera. 305 



lowering them to the normal resting position. In these 

 butterflies after the wings are thrown back, but before 

 they are dry and stiff, there seems to be a temptation to 

 assume the Heterocerous resting position, and just as the 

 wings are all but dry, a separation of them occurs, suggest- 

 ing the Hesperid position, with hind- wings only, lowered. 



I add more detailed notes of some of the species ex- 

 amined, and include the actual times of the several phases 

 as jotted down in the cases of two of the butterflies, where 

 the movements are more complex than in the moths — 



Oudemans' paper on the resting attitudes of Lepidoptera, 

 published in 1903,* suggests a number of species on which 

 observations might be made. 



Leucophthalmia orbicularia having rather rapidly ex- 

 panded its wings, closed them dorsally in the usual manner ; 

 it kept them so for some twenty minutes and then deflexed 

 them, nearly flat to the surface to which the moth was 

 adhering, but not pressed down on it ; the fore-wings had 

 their inner margins nearly but not quite parallel; that is, 

 they were slightly apart at the anal angles, so as to show 

 the body and a very narrow strip of the inner margin 

 of the hind-wing, not unlike the resting attitude of 

 Odezia atrata. It maintained this attitude for an hour 

 and twenty minutes, and might have done so longer, but 

 a jerk given accidentally when observing it, made it 

 flutter as if to take wing. It then settled down a few 

 inches away in the ordinary resting attitude, i. e. with 

 the wings flattened closely to the surface on Avhich it 

 rested, and the fore-wings advanced so as to show some 

 two-thirds of the hind-wings. (Plate LXXX. fig 2.) 



June 27th, 1916. — A Set. bilimaria $ had completed the 

 expansion of the wings, which were thrown back in the 

 usual I.epidopterous attitude of drying the wings, and 

 which is also the usual rest attitude in S. bilimaria, at 

 10.50. At 11 the wings were deflexed, not to a horizontal 

 position, but to an angle of about 120° between those of 

 the two sides, or of about 30° above horizontal on each 

 side — horizontal with reference to the line of the insect's 

 body, supposed resting on a flat horizontal surface. As 

 a matter of fact, the insect was suspended on a vertical 

 surface, the head hanging back from it, so that the line 

 of the body was an angle of about 25° from the vertical, 



* " Verhandelingen der Koninklijke Akademie van Weten- 

 schappen to Amsterdam " (2 ,le sect.), Deel X, No. 1. 



