FUNCTIONAL PROPERTY OF TONING MUSCLE IN Mingming CICADA (Oncotympana maculaticollis Motsch)
鸣鸣蝉(Oncotympana maculaticollisMotsch)调音肌的功能特性

In the Mingming cicada, the structure of toning muscle (TMc) and its connection with sounding membrane (SM) are given, and the toning function of TMc is also revealed in this paper.The front and back branch es of TMc are respectively connected with the bottom outside and inside of the anterior plate of SM and it is conducive to pulling SM. An angle between the lon-gitudinal axis of TMc and membrane surface of SM is about 120°. The downward vertical-pulling force to SM and forward horizontal-pulling force along the membrane surface may be about 87% arid 50% of the total pulling force respectively in a theoretical appraisal.The TMc possesses the significant toning function. It has an effect not only on pulse amplitudes of the two pulse trains (PT) produced by SM on each side, i.e. the amplitudes of the first and second pulse in each PT decrease by about 3-10 dB on an average, but also on the uniformity of sounding process in SM. Moreover, it has a s-gnificat effect on amplitudes of peak frequencies o the second upper partial in song spectra, ex. the amplitudes of 16756-17090 Hz decrease by about 16.3 dB on an average.