404 THE CANADIAN ENTOMOLOGIST. 



length of flight on this occasion to the absence of females, for it would 

 appear they only fly long enough to find and select a partner, and mating 

 takes place immediately. The next night an early start was made to 

 search the bush before dark, our object being to try and find them before 

 it was time for them to fly. This was successful also, for both imagoes 

 and pupae shells were secured, the former on the stems of the Willow, and 

 the fresh pupae shells on top of the ground. On this occasion, as on the 

 following night, the flight was very short, and females were plentiful ; lo 

 specimens were taken on the i8th, and on the 19th 18 specimens of thule 

 and a fine specimen of Sthenopis quadriguttaius were added. A careful 

 search of the bushes after dark gave us four pairs in copulation. This was 

 something nevv to us also, and was taken advantage of the following night 

 with good results, moths being secured before it was time for them to fly. 

 July 19th and 21st were unfavourable for collecting, owing to wet weather. 

 July 20th, however, eight specimens were taken, and on the 22nd four 

 more were added, and this proved to be the last, for although the search 

 was kept up, none were seen after that date. On that evening a number 

 of Sphingidae were seen at the Willow, and three or four specimens were 

 taken. We were about to give up the pursuit on account of darkness, 

 when we saw something hovering about the top of the bush, gradually 

 working its way to the other side. By a quick turn and swing of the net 

 my son managed to land it, and to our surprise it was a female thule. 

 We had never seen one fly like this before. The dates of flight herein 

 mentioned are somewhat late, but I attribute this to the unusually late 

 spring and cool summer, and would be inclined to say that under anything 

 like normal conditions their appearance would be from about July 8th to 

 the 20th. The time of flight each night is on an average about fifteen 

 minutes, and none were seen on the wing before 8 p.m., and not later than 

 8.30 p.m., with the exception of the specimen we have referred to taken 

 at light. 



Our efforts were well rewarded, for in all 75 specimens were taken, 

 and a little information gained as to the habits of Sthenopis thule. 



Note.— It was the unanimous opinion of those present at the meeting 

 when this paper was read that such wholesale captures of this rare moth 

 were most strongly to be deprecated. Collectors should be satisfied with 

 a few specimens annually, and not run the risk of exterminating a most 

 interesting species, which is only known to frequent a few very limited 

 localities. — Ed. C. E. 



