upon lepidopterous larva, dc. 309 



growth. The time of emergence and the habit of 

 hybernation in the perfect stage correspond with the 

 period of year at which the resembled objects form a 

 predominant feature in nature. The moth is eagerly 

 pursued and keenly relished by birds, so that it is of the 

 greatest importance that the protective resemblance 

 should be as perfect as possible, and that any in- 

 dispensable structure which would interfere with the 

 resemblance should be as far as possible concealed in the 

 attitude of rest. On examining the moth I was very 

 interested to find that the eyes are completely covered 

 by a tuft of long hairs, which droop from the base of the 

 antennas when the latter are directed backwards, and are 

 themselves concealed beneath the wings in the protective 

 attitude. When the moth is about to fly the antennas 

 are brought forward, and the same action raises the 

 tufts and uncovers the eyes, so that both pairs of sense- 

 organs are rendered efficient simultaneously. The base 

 of the left antenna, with its tuft of hairs, is shown in 

 Plate X., fig. 16, x 24'5. It is likely that the tufts 

 may be of use in defending the eyes from dust, &c, as 

 well as in preventing the brilliancy of these organs from 

 interfering with the protective resemblance. Instances 

 of an analogous arrangement, with the latter significance, 

 are found in the gecko and the chamasleon, the strong 

 protective resemblance being in these cases necessary 

 for the capture of prey rather than the avoidance of 

 enemies. The capture being largely dependent upon 

 sight, the eyes are very large, and would tend to render 

 these animals highly conspicuous. Hence in the gecko 

 the pupil is (except in dim light) a narrow chink with 

 very irregular margins, while all the rest of the exposed 

 part of the eye is coloured in such a manner as to 

 harmonise with the general surface of the animal, 

 rendered inconspicuous by its strong resemblance to the 

 stone which it frequents. In the chamaeleon the arrange- 

 ment is even more perfect, for the large eyes are covered 

 with skin, except for a small aperture opposite the pupil, 

 through which the animal can look. This skin is 

 directly continuous with that of the rest of the body, 

 and, like it, can be changed in tint so as to correspond 

 with the colour of surrounding surfaces. 



