1900. } INSECTS OF THE ‘f SKEAT EXPEDITION.” 859 
the former the exhibition of brilliant colour is primarily a sexual 
attraction, being better developed in the male than it is in the 
female ; but it seems probable that even in Liolepis any excite- 
ment 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 than the 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 which 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 teniwrus, will snap at anything, even at their 
own bodies, when they are sufficiently enraged. The Malays say 
that Dipsadomorphus 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 inter- 
mediate 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 opera- 
tion at Ban Nah, 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 Cicadie flew 
[23] 
