VALIDITY OF SOME FORMS OF MIMICRY. 707 



where Calotes is abundant, and almost all those which occur at 

 Nuwara Eliya, the fauna of which is very poor. 



Experiments with Lizards in Colombo. 



The two species of reptiles experimented on belonged to the 

 genus Calotes (C. ophlomachus and C. versicolor), or blood-sucking 

 lizards as they are commonly called. In appearance and habits 

 they are fai- more like Chameleons than ordinary Sand-Lizards, 

 and like them have the faculty of changing colour and assuming 

 on occasions brilliant scarlet, yellow and green, particularly about 

 the head ; but on the other hand they are very quick in their 

 movements and can run with considerable speed. They are 

 usually to be found sitting on walls and palings, clinging to the 

 stems of the longer grasses, and frequently lying in wait for their 

 prey behind the umbels of flowering shrubs, where their gaudy 

 colours help to deceive visiting insects. In such positions they 

 will wait motionless for hours on the chance of prey coming 

 within reach. But as I was unable to devote a whole day for 

 such prolonged investigations, I adopted the following method as 

 being the nearest approach to natural circumstances. I attached 

 a defunct or moribund butterfly by a long line of fine silk to a 

 fishing-rod, and thus succeeded with the help of the wind in 

 bringing the fly within reach of the reptile. The following were 

 the results from the end of November to the end of December 

 1908, with the notes I made at the time. 



November 24. A male Papilio p)olytes was waved over a green 

 Calotes ophiomachas which was clinging to some grass. The lizard 

 became slightly excited and made a grab at the insect, biting out 

 a piece of the fore wing and immediately eating it ; a second time 

 it bit a piece out of the hind wing including the tail ; the insect 

 if alive would certainly have escaped on both occasions. Finally 

 it seized it by the head and ate the remainder. 



November 30. A female Papilio polytes of the black and white 

 variety offered in the same way to another Calotes. This lizard, 

 which was evidently hungry, became excited when he saw the 

 butterfly, and made a grab at it and bit out a piece of the fore wing 

 Avhich it promptly began to eat ; the butterfly would have 

 escaped. While this "fishing" was going on, a male butterfly 

 attracted by the female flew quite close to the lizard, which made 

 a dart at it and tore away a piece of its wing, and the butterfly 

 flew off. A lizard grabs at any part of the buttei'fly that comes 

 within reach, and as the gi'ass sways when it moves it is quite 

 a chance what part is seized ; the habits of Calotes therefore 

 negative any theory of so- called directing marks so far as they are 

 concerned. 



November 25. The wings of the black and white variety of 

 P. polytes ai'e quite common in the garden, and I am quite sure 

 the Calotes devour great numbers of them. I saw C. versicolor 

 with a live one in its mouth ; on this occasion it was holding the 



