ANIMAL BEHAVIOR, WITH EXAMPLES 215 



In flight, this insect, Uke others of this interesting group, 

 has a singular habit of hanging the hind tarsi out behind its 

 body, in the manner I have depicted him. Like many insects 

 of rapid flight, the extreme vibrations of the wings cause them 

 to appear Hke a haze on either side of the body. I have 

 attempted to give this in my drawing. With marvellous 

 agility he uses the wings much as a large bumblebee would, 

 though his flight has much more speed and is under better 

 control. We are all famihar with the manoeuvres of the large, 

 black horse-fly, Tabanus atratus, that can outstrip the speediest 

 animals. 



The present species is nearly as large as the horse-fly, and 

 his strong wings give him the power to turn about in the air 

 with great celerity. There is a striking contrast between him 

 and his more delicate, day-flying relatives, the Syrphus flies, 

 some of which are of diminutive size. These flies may often 

 be seen hovering in the air, in their haunts in the shade of trees 

 or among shrubs and flowers. They are so tame that with 

 slight tact I have often tempted them to alight on the tips of 

 my fingers held up quietly toward them. But the Tabanid 

 fly is exceedingly alert. 



Some of our readers may have witnessed the aerial perform- 

 ances of this species, and, if so, may be able to tell us whether 

 it is one connected with their sexual dances, or merely one of 

 play. The humming sounds of some male flies have been 

 observed to win the females by their music. One of a species 

 known as Eristalis has been seen by Mtiller courting a 

 female by hovering above her and flying from side to side, 

 making a high humming sound at the same time. 



The Hunted Cicada 



The drumming notes of the cicada, or dog-day harvest-fly, 

 are heard for the first time about the latter part of July, though 

 the time varies somewhat in different years. I heard one, 

 in the afternoon of July 20, 1905, trying its long-drawn-out 

 song, but it seemed to be unable to carry out the full continuous 

 drumming. It may be that this was the first trial after emer- 

 gence from the pupa, for I had not heard many calls before. 

 From this time on, trillings were heard for weeks afterwards. 



