206 



THE AUSTRALIAN MUSEUM MAGAZINE. 



This cynical reflection serves to impress 

 upon us the im])ortant fact that the 

 sound-producing organs occur only in 

 the male. These are situated on the 

 upper surface of the first segment of the 

 abdomen. The sound is produced by 

 the bending of a stiff horny membrane 

 which is acted upon by a muscle. The 

 same effect is produced if one rapidly 

 buckles the bottom of a kerosene tin 

 backwards and forwards. The opercula, 

 or " drums," as they are wrongly 

 termed, which are seen on the ventral 

 surface of the abdomen as thin plates, 

 probably serve as resonators but have 

 nothing to do with the production of 

 the sound. When singing, the Yellow 

 Monday usually lowers his wings from 

 their roof-like position and elevates his 

 abdomen. 



The Yellow Monday has, in common 

 with other species, been the plaything 

 of the boys of Sydney, probably since 

 the earliest days of the colony. The 

 unfortunate insect is subjected to every 

 indignity and abuse that childish in- 

 genuity can devise. An outrage fre- 

 quently perpetrated by juvenile offen- 

 ders on the defenceless " locust," is to 

 insert a blade of grass into its body, 

 then to liberate the victim and watch it 

 fly into the air with the long appendage 

 trailing behind it. A more common 

 practice is to take them into school, 

 where they serve to enliven the some- 

 what dull proceedings of a lesson by 

 giving vent to loud protesting squarks 

 in response to an occasional shake by 

 their captors. Every Sydney school- 

 master during some time of his career 

 has had cause to execrate these noisy 

 insects. Not even during its " pupal " 

 period is the locust safe from these 

 young marauders, for in our parks 

 during the summer it is no uncommon 

 sight to see small boys carrying bottles 

 of water and searching most diligently 

 for cicada burrows. These they flood 

 with water, causing any pupae that may 

 be within to ascend to the surface of 

 the ground, where they are promptly 

 secured. 



LIFE HISTORY. 



The female cicada is provided with a 

 strong saw-like ovipositor, or egg-laying 



Portion of a eucalyptus branch ripped up by 



the ovipositor of the female when laying her 



eggs. 



[Photo.— G. C. Clutton. 



organ, by means of which she is able to 

 rip up the bark of small branches and 

 deposit her eggs in rows in the excisions 

 thus made. Little is known of the life 

 history of our Yellow Monday, but as 

 many cicadas lay about three hundred 

 eggs, it is generally supposed that she 

 lays about the same number. 



When the young cicadas emerge from 

 the eggs they are tiny and shrimp-like 

 in appearance. They make their way 

 to the ground, many falling off the 

 branches. On reaching the ground, they 

 work their way down to the roots, where 

 they pass the greater part of their life, 

 deriving nourishment from the sap. 

 The length of time passed underground 

 has been estimated at three years, 

 since they are most numerous every 

 third year. An American species. 

 Cicada septendecim, spends seventeen 

 years of its life underground. During 

 its subterranean existence the cicada 

 moults many times, but in the case of 

 the Yellow Monday this important 

 detail of its life history still remains 

 undiscovered. 



