The investigation of the Morphological base with the mechanism of the sound of the cicada’s song is still devoid of data in China.Cicada’s song belongs to low energy but high effect.We atlempt to apply the information of the song to the practice by the yiewpoint and means of the bionics. The immersion specimen of sixty of male cicada was morphologically observed under the binocular.Twenty live cicadas were cut or destroged respectively on the both sides

and we measured the range of the song intensity 31

5—16

000Hz dB(A) and surveyed the relationship toetwen the sound-producing organ and the effect of all the structures. In normal condition

the tympals are in out-side convex

while the tympals’ muscle contra- cts

it pulls the tympals in wards

viberating the air of the tympal cavity and bringing about the sound.When the muscle relaxs

the tempal goes back to its orignal position

depending on its own elasticity and ir turns toward outside again

vibrating the air of the tempal cavity and gi- ving rise to Another kind of sound.The sound of the cicada may produce the changes of the high and low pitchs and the strong and week sounds

with the change of the frequencey and amplitude of the repeadly fast-speed viberation.Through the eaculating of the statistics of the twenty cicada’s songs

we have discovered that in the change of the sound

there is ext remely striking meaning(F=31.9 p<0.01)between the normal cicada and the one destro- yed in structurs such as mirror membrane

folded membrane

dorsal valve

tympal and abdominal valve. Compared with the normal cicada’s song: Mirror membrane of the two lateral sides destroyed

it is of abvious significance (Q=2.831

p<0.05). Tympals of the two lateral sides destroyed

the difference is of extremely striking meaning in statistics (Q=13

193

p<0.01).