INVESTIGATIOiSrS ON THE MUTILLID WASPS 27 



which naturally occurred to me was the thought, Why has nature, which 

 does not do the least thing without a wise purpose, given this insect such a 

 voice and why does it need this signal, since it does not go more than three 

 steps from its home during its whole life? I busied myself with this thought 

 as I approached a beehive to secure a bee in order to investigate this. But I 

 did not get hold of it in the proper way and it made a noise with its wings ; im- 

 mediately so many workers came up on me that I did not wait to look around. 

 This occurrence explained the puzzle to me, thus, that the benevolent nature 

 had presented these wingless Mutillids this sound for speech in order to call 

 out their brothers when they are in danger. If the others are able to fly away 

 from danger and are able to give an alarm with their wings, then this pedes- 

 trian, this bird without wings, can call with a loud voice as well as use itp 

 sting. I convinced myself very authentically of the true basis of these con- 

 clusions. As I enjoyed a recreation hour and watched these differently 

 formed dwellers in the earth flying in and out, and their wingless little wives 

 go walking in the grass a few steps from their nest in the bright sunlight 

 (which is their entire journey) I picked up a Mutillid and forced it to make a 

 sound. Its own male not only came hurrying out immediately, but also the 

 bumblebees and forced me to let my prisoner go free. 



Goureau (1837) verified Christ's observation as to how the sound 

 was produced with the correction that it was made with the second 

 and third abdominal segments, rather than the first and second. One 

 may legitimately assume that the purpose of a stridulating organ 

 such as both sexes of the Mutillids possess is for the purpose of com- 

 munication between the sexes. Peringuey {1899a) reports an obser- 

 vation made by the Kev. J. A. O'Neil that seems to confirm this 

 assumption. 



The Rev. J. A. O'Neil has hit upon a very interesting mode of capture of both 

 sexes by the so-called " sembling " method. He finds that by seizing hold of 

 the female in such a way as to induce her to produce her well-known stridu- 

 lating noise, the males immediately appear and swarm round, and even settle 

 on the hand of the captor, and are easily secured. In that way he obtained 

 both sexes of M. cloantha and M. hecuha, and the identity of the last-named 

 species has been verified by the capture in coitu made quite independently by 

 Doctor Brauns. 



Rasanen (1915) has studied the stridulation apparatus found in 

 some species of ants and states that the structures found there are 

 similar in many respects to those found in the Mutillids. 



While this stridulating organ has been noted and described a 

 number of times no one seems to have observed any organ of hearing 

 in the Mutillids. At the present time there is nothing to indicate 

 what the nature and location of such an organ of hearing may be. 



GYNANDROMORPHISM 



Four cases of gynandromorphism have been observed among the 

 Mutillidae. The first case to be observed was reported by Maeklin 

 (1856) regarding a specimen of MutilJa europaea var. obscura 



