Observations on the habits and natural surroundings of insects made during the 'Skeat expedition' to the Malay peninsula, 1899-1900 / by Nelson Annandale.

Nelson Annandale

Date:: 1900

Credit: Observations on the habits and natural surroundings of insects made during the 'Skeat expedition' to the Malay peninsula, 1899-1900 / by Nelson Annandale. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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$centre and not towards the periphery; but, nevertheless, it was striking and, at a first glance, quite deceptive. When disturbed the caterpillar commenced to walk along the leaf, slowly and irresolutely, unbending and rebending its long thoracic limbs as it moved, and shaking the two processes with which its abdomen terminated. I took it home, and shut it up till the next morning with a supply of leaves, hoping to photograph it when the light was better. During the night the insect cast its skin, and in the morning all likeness to anything else had left it. The skin was no longer polished and glittering, and the colour had changed to a dull brown with dingy white bars. Moreover, all sluggishness of movement had disappeared, and the caterpillar was now ex- ceedingly brisk, behaving very much as a well-grown specimen of our own English form would do. During the languor and dangerous inactivity of the ecdysis and the period immediately preceding it, protective coloration had been assumed ; as soon as the operation had been safely performed, the habitual means of defence were adopted once more. But to return to animals which, being otherwise inconspicuous, have the power of exhibiting brilliant colour when alarmed. This phenomenon is not only exemplified by insects. A good instance is that of the Toad Callula pulclira, which is found not un- commonly in the Siamese States, among the rubbish which collects under the houses and in like situations. In this species, the upper surface of which is otherwise of a warm brown colour, a broad yellowish stripe runs along either side of the back; but the peculiar looseness of the skin and the folds into which it naturally falls prevent this stripe from becoming conspicuous. When the animal is disturbed, however, it draws air into its lungs until its body becomes almost globular, and the skin is stretched in such a way that its contrasting colours are displayed to their best advantage. We may compare this amphibian to the fish of the genus Tetrodon and others, which have earned the name of Balloon-fish among Europeans, and of “ IJcan hunted’’ or Pillow-fish, among Malays, by the manner in which they gulp down air into their stomachs, so causing the brilliant coloration of many of them to become conspicuous, and also the spines with which they are armed to be erected. Another interesting example is afforded by the Lizard Liolepis hellii, which the Malays call “ Biavjalc Pasir ” \ or Sand Monitor, and which is common in all sandy plains where the vegetation is scanty in the north of the Malay Peninsula. The male of Liolepis is coloured in what sounds a very gorgeous fashion, and what is in nature by no means a conspicuous one. The upper surface is grey, mottled and eyed with green, the lower surface pale yellow veined with blue, which is more conspicuous on the underside of the thighs and the neck than on the rest of the body. Along each side there are a number of transverse bars, alternately of orange ^ BiawaJe is the Malay name of Varanus. [21]$