ACRONYCTA ALNI. 17 



it was content to lie up and moult on a leaf of alder, it 

 left it to feed again on oak. On the 12th of August it 

 was full-fed and began to excavate its puparium in a 

 piece of rotten wood, and closed up the entrance in the 

 evening. The seven larvae fed up separately from the 

 2nd to 12th of August, and six perfect moths appeared 

 in 1882, viz. on June 6th, a g; June 7th, two c? ; 

 June 9th, a ? ; June 11th, a S (these last two I 

 paired) ; and on the 17th June, two ? . 



I put the S , which emerged like most of the others 

 about midday, to the ? the same evening, when copu- 

 lation ensued almost immediately, and when fairly 

 coupled I let them remain for the night. In the course 

 of the next day, when I saw they had separated, I 

 removed one from the other, intending to have the S 

 as a cabinet specimen, but when they were in separate 

 pots I felt puzzled to know their sex, as the shape of 

 the abdomen and their antennas seemed alike. 



In this uncertainty I fed them daily with sugar and 

 water, expecting the appearance of eggs to decide which 

 was really the female. I could see that one moth was 

 rather larger than the other, and while I waited the 

 smaller had become so riotous as to spoil the wing 

 fringes. After three days I found two eggs were laid 

 by the largest moth, and from their appearance I had 

 some doubt whether they were fertile. After a week 

 had passed these two eggs, and four others laid subse- 

 quently, had not changed colour and were shrivelling 

 up, quite sterile. 



Accordingly, in the evening of the 18th of June I 

 returned the male insect to the company of his former 

 mate, and just as at first, a week before, they again 

 coupled immediately, and were left alone, and I decided 

 to let both remain together as long as they might live. 



Eggs now began to be laid, at first sparingly, then 

 more numerously, on alder and oak leaves put for the 

 purpose, and a few were laid on the side and bottom, 

 and on the ieno cover of the pot. The egg-laying 

 took place every evening at dusk, while on the wing 



VOL. iv. 2 



