1909.J 132 



OBSERVATIONS ON EM PIS OP AC A, F. 



BY A. H. HAMM. 



Reprhited from 'The Entomologist's Monthly Magazine," 2nd Series, Vol. xx. 



Last year in making observations on Empis livida I also en- 

 deavoured to study other species of the same and allied genera. In 

 this attempt I was unsuccessful, the weather being unfavourable or 

 the season too far advanced. I have, therefore, been looking foiward 

 to this season in order to continue, if possible, the work begun last 

 year. For several past week-ends I have sought unsuccessfully to 

 find some of the earlier species. Yesterday (May I6th) I at last 

 came upon a spot where this insect {Empis opaca) occurred in some 

 abundance, along a rather high hedge bordered on either side by 

 sandy fields, at Lye Hill, near Cowley, Oxford. At 11.20 a.m. I 

 found a male with prey ; it was carefully boxed, without disturbance, 

 so that the manner of holding the victim might be studied. Through 

 the glass-bottomed box it could be seen that the prey was held by the 

 two intermediate legs, both anterior and posterior pairs and the pro- 

 boscis also being quite free. I afterwards noted the same in other 

 individuals seen at rest. Numbers of both sexes were observed 

 sitting about upon the low herbage, but not one was seen to move ; 

 for a strong cold wind was blowing down the hill, making the 

 conditions very unpleasant. After waiting some little time I moved 

 off to try and find the species in a more sheltered place, but after 

 more than an hour's fruitless search 1 returned to the original spot. 

 It was now about 1 p m. and the weather had improved, the sun beino- 

 fairly bright. I soon saw that the Empids were now on the move, 

 and at 1.5 p.m. had the satisfaction of witnessing a male (with prey) 

 pair with a female. The actual pairing took place in the air, after 



