256 SCIENCE PROGRESS 



changes from a bright blue creature into apparently a dead 

 leaf ; the enemy failing of course to realise that such a change 

 has taken place, continues to look for a bright blue insect 

 (Marshall, Trans. Ent. Soc. 1902, pp. 355, 363). This method 

 of protection is very widely made use of and probably accounts 

 for many of the brilliant colours which are concealed when 

 animals are at rest but displayed during motion. There is 

 also evidence that two colours of great contrast are sometimes 

 used in this manner to heighten the effect : for instance, from 

 one aspect red is shown, then with a sudden change of position 

 blue is displayed, and finally settling, the animal displays only 

 protective colours. This must be contrasted with warning 

 colouration, which instead of being concealed at the last moment 

 is displayed either always or not until discovery by the enemy 

 is certain. 



It is, however, possible that this conjuring colouration, 

 although it cannot be a warning against unpalatability, may 

 nevertheless be warning or distinctive colouration against 

 difficulty of capture, and as such may form a model for mimicry. 



Blue in small areas remains to be dealt with : it occurs in 

 the Nymphalinae nine times and in the Papilionidse fourteen 

 times, in the Parnassiinae as small eye-spots of blue on a white 

 ground, in Orpheides demoleus and in several species of Papilio 

 as small blue spots forming a marginal pattern to the hind- 

 wing and associated with yellow. The occurrences of small 

 blue areas in the Nymphalinae are given in table No. 5 : 



TABLE NO. 5 



1. Stibochiona nicea . black insect with blue marginal eye-spots. 



2. Euthalia lubentina . small blue patch at margin of hindwing. 



3. Euvanessa antiopa . small blue patch at the junction of the wings associ- 



ated with yellow markings. 



4. Junonia hierta . 



5. Eugonia xanthomelas 



6. Aglais kaschmirensis 



7. A. rizana . 



8. A. ladakensis . 



9. Acidatia hyperbius . a marginal patch of blue, with black spots associated 



with orange markings. 



In many of these cases the arrangement of blue, especially 

 when forming a marginal pattern, gives rise to an incon- 

 spicuous appearance. It is remarkable that in many cases 



marginal row of blue spots associated with an orange 

 and black centre. 



