FREQUENCY CONVERSION PROPERTY AND DYNAMIC PROCESS IN SONGS OF Mingming CICADA (Oncotympana maculaticollis Motsch)

摘要

In this paper, the frequency conversion property Df Mingming cicada songs is revealedand its dynamic process is given. In every single call the prelude and coda are mostly mono-timbre sounds whose dominantsounds are mainly the basic sound （BS） with the main peak frequency of about 4000 Hz. Themajority of the loud songs consist of 5--8 vari-toned syllables （VTS） "Weiying". The process of frequency conversion consists of the pre-mixed tone "Wei", with BS as thedominant sound, mid-mixed tone and "Ying" with the inferior sound （IS₂） of 3--5 octave ofBS as the dominant sound. The inferior sound （IS₁） of 1.5--2 octave of BS is a sound accom-paniment of low intensity. In the process of frequency couversion, although no obviouschange occurs in the contraction frequency of sounding muscle （SMc）, about 220±25 Hz,obvious differences occur in the twitch property of it. BS, IS₁ and IS₂ are respectively excitedby quasi-sine and saw-tooth twitches. The velocities of upward and downward sound accom-paniment moveme