OCR Text |
Show 1900.] INSECTS OF THE " SKEAT EXPEDITION." 859 the former the exhibition of brilliant colour is primarily a sexual attraction, being better developed in tbe male than it is in the female ; but it seems probable that even in Liolepis any excitement may cause a display, and that in a secondary manner this display has come to be used as a means of alarming enemies, though it will be noticed that the conspicuous stripes are not exhibited suddenly, or immediately on disturbance, but only when the animal is handled. Also it is strange if the larger, more active male has this means of defence better developed thau tbe female, which must be much less agile at times. The fact that Liolepis bellii has particularly strong teeth and jaws does not seem to me to be of any importance in considering the case. The Cobra affords one of the best instances of alarming coloration and attitude, and it happens to be a particularly venomous animal; but there are instances of similar display among animals which have no such dangerous qualities. The. black-and-yellow Snake, Dipsadomorphus dendrophilus, which is the commonest large Snake in Lower Siam, when driven to extremities exhibits movements w7hieh may be compared with the sudden display of colour by other forms. If a specimen of this Snake is tied up so that it cannot escape, it raises its head, gapes, hisses, strikes wildly at anything that is held near it, and drums spasmodically upon the ground with the last few joints of its tail, thus producing a curious noise. But I have never seen it bite, even when a stick was held close to its mouth ; though many Snakes, e. g. Coluber tceniurus, will snap at anything, even at their own bodies, when they are sufficiently enraged. The Malays say that Dipsadomorpdius is not poisonous ; but they are much afraid of its bite, because of its violent appearance. V. SOUNDS PRODUCED BY INSECTS. A Cicada (Dundubia intemerata). There are two distinct colour varieties of this species, found together and independent of sex ; the body of one being grass-green, and that of the other pale brown, which becomes yellow as the insect dries. Among my dried specimens there are intermediate forms more or less mottled; but this peculiarity did not appear for some days after death, and in life all the individuals were either one colour or the other. At certain seasons this Cicada forms a regular article of diet among the Siamese inhabitants of Patalung ; and as their method of capturing it is based upon a knowledge of its habits, I cannot do better than give an account of this method, as I saw in operation at Ban Nab, a village on the border of the hill-country of Patalung. Immediately after the sun had set several of the natives gathered in an open space, round a fire of brushwood or a number of torches fastened to stakes stuck into the ground, and commenced to clap their hands in unison, observing a regular time and rhythm. Very soon, if they were fortunate, the Cicadae flew |