24 HABITS OF IMAGOS. 



them in the perfect state except fungi. Nor do they 

 seem to have any special external enemies. Birds I 

 have never seen feeding on them, but have often 

 witnessed combats between them and ants, carnivorous 

 beetles, and centipedes. 



The males appear five or six days in advance of the 

 females. The union of the sexes generally takes place 

 in the sunshine. It lasts only for a few minutes, after 

 which the female gets restive and kicks off the male, 

 who dies in a few hours after, while the female imme- 

 diately proceeds to deposit her eggs. From the struc- 

 ture of the copulatory organs, the <$ has to insert 

 them backwards ; and sometimes one may be seen 

 dragged about by the ? , attached only by the anal 

 appendages. 



So far as my observations go no selection is shown 

 by either sex in choosing partners. With Trichiosoma 

 I have noticed that the males, after emerging, and 

 apparently before the females have appeared, assemble 

 together on the tops of birches (with T. lucorum), round 

 which they fly in circles in the hot sunshine, making 

 as they do so a loud buzzing noise, not unlike the 

 humming of a Bombus. They do not fly far, and gene- 

 rally return after a short flight to the tree top from 

 which they started. I was once the witness of a 

 battle between two males of T. lucorum, which lasted 

 for nearly ten minutes, or perhaps longer, for they 

 flew away, and may have continued the fight after I 

 lost sight of them. Their mode of fighting was simply 

 to fly at each other in the air, a concussion of the two 

 bodies being the result ; and they must have come 

 together with some force for the noise made thereby 

 could be distinctly heard. I did not observe whether 

 they tried to use their mandibles or not, but Westwood 

 mentions (Intr. ii, 109) having caught two males with 

 their mandibles interlocked. And every collector 

 knows that these insects can use their mandibles to 

 some purpose. 



