COURTSHIP OF HEPIALUS HECTA, 195 



like those of its relatives or not, are more likely to be later acquire- 

 ments and not to possess much importance in settling its phj'logeny. 



Explanation of Plates. 



Plate XIII. — Fig. 1. — Portion of larval skin 1st instar x 120 



,, ,, ,, 2. — Two hairs of ,, 



,, ,, ,, 3. — Portion of ,, 



,, XIV.— ,, 4.— ,, ,, „ 



„ 5.— ,, ,, ,, 



,, XV.— ,, 6.— „ ,, ,, 



,, ,, ,, 7. — Two larvae in the last instar on spray of Celtis australis. 



,, ,, ,, 8. — Pupa of L. celtis. 



„ XVI. — ,, 9. — Hooks of right prolog of 5th abdominal segment. 



,, ,, ,, 10.— ,, ,, left ,, ,, ,, ., „ in last 



instar. 



,, XVII. — ,, 11.— Larval heads of 1st instar x 2-5 



„ 12.— ,, „ ,, 2nd ,, x25 



,, 13.— ,, ,, ,, 3rd ,, x25 

 14.— „ head of 5th ,, x 25 



Courtship of Hepialus hecta. 



By E. A. COCKAYNE, M.A., M.D. and F. W. J. JACKSON, M.A. 



Being anxious to confirm the observations on the pairing habits of 

 Hepialus hecta published in the KntoiiniliujufR Jtecord, vol. xxiv., p. 

 236-7, we visited the spot again on May 31st this year. At 7.35 p.m. 

 the first H. hecta appeared, flying rather slowly. As soon as it had 

 settled wc saw that it was a female, and looking round we noticed a 

 male at rest on a neighbouring rush, with wings closed and scent-sacs 

 exposed. 



The female soon took flight again and approached the male, but 

 swung off and settled two or three feet away and rested with quivering 

 wings. Altera few seconds she rose again and flew straight up to the 

 male and actually touched him, but then dropped and settled almost 

 on the ground. The male on being touched began to flap his wings 

 and finally held both fore- and hind-wings spread open. Then he 

 held the wings on the right side tightly closed while the left forewing 

 was held out and constantly agitated. The female again flew up and 

 soon approached the male, but failed to pair, and finally came to rest 

 on a rush a few inches away. Meanwhile we had noticed another 

 male flying pendulum-wise some yards away. After a short time he 

 had approached the first male, and then flown off to a rush two or 

 three feet away where he had alighted and remained with the 

 forewings held almost at right angles to the body, and the hindwings 

 closely applied to it in the attitude commonly adopted while waiting 

 for a female to approach. Immediately after the last attempt of the 

 female to pair with the first male, the second took flight again and 

 went straight to the female, settled just below^ her on the same rush, 

 ran up and paired. After pairing be let go at once and hung sus- 

 pended with legs and wings folded up. 



We have given a full account of the incident, because cases of this 

 kind are unusual. Sexual instinct is very fixed : in most species 

 the male invariably seeks the female, in a few the female the male. 

 Occasionally however females are caught by assembling as happened 

 to one of us at Eannoch some jears ago, where a female Troclulium 



