m 



THE ENTOMOLOGIST. 



CONTRIBUTIONS to the CHEMISTRY of INSECT COLOURS. 



By F. H. Perry Coste, F.C.S., F.L.S. 



(Continued from p. 119.) 



V. — The Chemical Aspect (continued). 



I. 



Before saying anything as to the nature of blue in the 

 various species examined, I will first subjoin, as in the case of green, 

 a list of a few exotic Lepidoptera on which I have been able to 

 experiment since my tables of results were published last August. 



Name. 



Acid effect. 



Alkaline effect. 



Morpho menelaus 



Trepsichrois linncei \ 



("iKis" purple) J " 

 Hypolimnas bolina ] 



("iris" purple) j " 



H. salmacis (violet) 



Papilio polyctor (crescent 



marks) 



P. polyctor 



P. philenor 



P. nireus 



Less brilliant 



Less brilliant or 

 The glow dulled 



(0) or much dulled, &c. 

 Duller or 



Same as acid 

 iNOg, specimens recovered 

 Lve days.) 



Leaf-brown 



The velvet " glow " dulled 



(0) 



Duller 



Sort of " yellow " 



(All, except the HCl and I 

 within £ 

 Leaf -brown 



Bronze 



(Becovering, in a few days 

 blue or a bi 

 Steel-blue or steel-violet 



Bronze 



either the original bright 

 ight green.) 

 Same as acid 



P. sarpedon 



P. pliorbanta 



P. leonidas 



Transparent* or 



Steel-blue or violet .... 

 Partly transparent .... 



Paler or transparent 

 Same as acid 

 Partly transparent 



We will next, following our usual plan, arrange these blue 

 species into groups ; but, as will appear from the sequel, it is 

 questionable whether all, except perhaps the LyccencB, might not 

 be put into one single group. 



1. 



2. 



3. 



4. 



5. 



Apatura iris 

 Trepsichrois 



linncei 

 Hypolimnas 



bolina 



Papilio 



philenor 

 P. polyctor 

 P. nireus 

 P. pliorbanta 

 P. sarpedon 

 P. leonidas 



(addendum) 



Morpho 

 menelaus 



Papilio. 



machaon 

 Limenitis 



Sibylla 

 Smerinthus 



ocellatus 

 Catocala 



fraxini 



Vanessa urticce 

 V. atalanta 

 V.io 



V. antiopa 

 Papilio 

 polyctor 

 (the crescent 

 marks) 



Lyccena alexis 

 L. corydon 

 L. adonis 

 L. semiargus 

 Cupido bochus 



6. 



H. salmacis 



Nitric acid had the extraordinary effect of changing this into a pink. 



