526 
NOTES ON CICADAS. 
By Walter W. Froggatt. 
Regularly every season as the warm summer days set in, toward 
the latter part of the year, the shrill call of the Cicadas, or "locusts " 
as they are popularly called, is heard with monotonous regularity 
in every cluster of trees or shrubs about Sydney. It is noticeable 
that every third year they appear in much greater numbers than 
in the two preceding seasons; and with the well known fact 
before us that the American "Seventeen-year Cicada" (C. 
septemdecim) reappears every seventeenth year, I am led to the 
conclusion that several of our larger species take three years to 
reach maturity. 
During this last season (1894-5) they appeared in countless 
numbers all round the neighbourhood of Sydney, and were much 
more in evidence about the suburbs than they had been for many 
years previously. The paddocks about Croydon were literally 
covered with the tubular holes through which the pupse had 
escaped, while every tree trunk and fence was festooned with the 
dry larval skins split down the middle of the back and firmly 
fixed in position by the powerful claws of the fore legs. For fully 
three months they kept up one continuous screech, unless a 
thunder storm sprang up, and then every Cicada was mute. 
Acting on a suggestion made by Dr. Cox at one of our meetings 
some time ago [Proceedings iii. (2), p. 1508], I jotted down a 
number of observations made in the bush under these very favour- 
able circumstances, of which the following notes are the result. 
At Croydon the first Cicada was heard on the 30th of October 
about sunset, and a few days later I caught several of the small 
black ones (Melampsalta melanopygia, Ger.). In February their 
dead bodies began to be plentiful under the trees, and the calls of 
the survivors were fitful and irregular, according to the state of 
the weather, being heard only on fine days. The last heard at 
