160 
Psyche 
[June-September 
We recorded the calling song of a C. monstrosa specimen (Figure 
6, 75-6) before and after damaging with a scalpel, several teeth in 
the central region of his right tegmen file. In oscillograms of post- 
mutilation recorded song, his use of the damaged file (i.e. right 
above overlap) was apparent as a drastic mid-pulse drop in ampli- 
tude. In one oscillogram, a portion of which makes up Figure 6 
(second trace from bottom), 20 pulses in succession were ‘right 
above’. 
Switch-wing singing as suggested by distinctive pulse envelopes 
within the same trill was only evident in our records on one 
occasion. A male of C. monstrosa had been released in the 
immediate vicinity (i.e. within antennal range) of a mature female 
on the observer’s hand. He began to sing while walking about on the 
hand and directing his attention toward the female. His song was 
recorded and on analysis found to be a trill in which every other 
pulse was identical in envelope and distinctly different from the 
intervening pulse i.e. there were two pulse types occurring in 
alternation without break in the sequence of the trill (Figure 6, 
bottom trace). This was apparently a courtship song. 
It is clear that pulse envelopes are highly variable in the genus, 
though usually quite consistent for a particular recording session of 
a particular individual. Switch-wing stridulation is probably not an 
everyday feature of C. monstrosa calling song but it may occur 
under special circumstances such as courtship. 
Oscillograms of normal calling songs are given in Figure 6. The 
pulses of C. strepitans and C. buckelli are apparently indistinguish- 
able. They are usually wedge-shaped: each begins with a steep rise to 
maximum amplitude, then falls steadily to the pulse’s end. The 
pulses of C. monstrosa also have a steep onset but are usually of 
longer duration. They are drawn out in an uneven envelope near 
their maximum amplitude before dropping away to silence. 
Carrier frequency spectra of all three species are highly similar. 
Specimens were analysed ‘live’ (i.e. without tape-recording) by 
directing the output of a Bruel & Kjaer sound level meter (2204) 
fitted with a !4" microphone (4135) into a Tektronix 3L5 spectrum 
analyser. This system will detect ultrasonic frequencies up to 100 
kHz. No substantial sound energy exists in the ultrasonic range for 
any of the Cyphoderris species. The sinusoidal nature of the 
waveform is apparent in the narrowness of the dominant frequency 
