| Abstract: | Adults of Extatosoma tiaratum liberate a strong smell when handled. The smell is associated with a colourless, volatile liquid which is apparently harmless to man. It is ejected on to the thorax of the insect, and on to the hands of the investigator, from a pair of tubercles located on the anterior border of the prothorax. The tubercles have a slit-like aperture through which the secretion is sprayed on attack. The secretion is produced by two glands in the thorax, each comprising a pair of tubes which unite just beneath the tubercle. The tubes consist of a thick, glandular epithelium lined with a thin layer of cuticle; most of the gland is enveloped in a layer of muscle. The defence reaction is discussed in relation to that of other phasmids. |
