This is the song of Phyllopalpus pulchellus, a beautiful little cricket that sings primarily during the day in the summer. Notice the pulses come in groups but not regular groups, sometimes pairs of pulses, sometimes 3 or four. It looks as though certain pulses have simply been dropped from the song, as though the CPC has skipped a tick. However, it is not that simple. At the bottom is the distribution of pulse periods in 10 secs of song. It is bimodal with a one mode, corresponding to the shorter periods of the song, having an average of about 18 ms. The second mode is more variable and the mean is much less than twice the mean of the other distribution. If these rhythms are generated by a CPG it is much more complicated than would be expected for a species that trills.