Selenocosmia crassipes, the so-called barking spider of Central Australia and the inland areas of New South Wales, is said to produce a barking sound. These reports were investigated by Sir Baldwin Spencer, who, although he rejected the barking theory, found that the spider produced a chirping or whistling sound by drawing the leg-like feelers or palps across the fangs (chelicerae). Examination under the microscope proved the palps to be studded with a great number of peg-like structures by which the sound is produced. This strange habit has possibly a courtship significance. It is regrettable that no further attempt has been made to study the life and habits of this remarkable spider, but this is true of many of our unique and rapidly disappearing animals

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