CLASSIFICATION OF THE LEPIDOPTERA PAP1LI0NINA. 295 



of comparison, unless the difference is capable of actual measurement 

 and is constant to the practically same extent in all tho species grouped 

 under them are similarly unsatisfactory. 



It will be seen at once that in Lepidopteroua insects the neuration of 

 the wings is likely to be of exceptional value as being least exposed to 

 external influences and experience shows that this is the case. Except 

 in tho case of the more degraded groups of the TINEINA and of the 

 Pterophoridae there are singularly few instances where any 

 important modification can be directly attributed to an alteration in tho 

 shape of the wing. It may be added that in no other order is it so 

 easy to trace the philogeny by this means as in the Lepidoptera. 



The most generalised group in the Lepidoptera is admittedly the 

 MICROPTERYGINA. The gap between these and the next most 

 primitive forms is undoubtedly wide; but the descent from the Tineidse 

 — through the Heterogeneidae — of the Thyrididae in which family 

 we must recognise the ancestors of the P API LION IN A is clear and 

 continuous. 



The PAPILIONINA are at present a rather isolated group though 

 the gap between tho oldest forms of the Hesperiadae and the 

 Thyrididae is probably not greater than that between the former 

 and the rest of the group. Nearly all the peculiar characteristics of the 

 group can be traced more or less directly to adaptation to diurnal habits 

 and this is particularly marked in the later forms. 



CHARACTERS. — Head, ocelli and maxillary palpi obsolete, tongue and 

 labial palpi developed, antennae simple more or less dilated apically- typically 

 with a regular formed club. F.W. 1 a. and 1 c. absent 1 b. simple H.W. without 

 frenulum, 1 c. absent, 8 rising out of cell near base thence rapidly diverging. 



The 7 families may be tabulated as follows : — 



1. With all the veins present and separate V Hesperiadae. 



With 2 or more veins stalked or coincident. . 2 



2. Both sexes with the anterior legs aborted ... 3 

 Anterior legs developed in one or both sexes. 4 



3. Vein 12 of F.W. greatly dilated at base 2 Satyridae. 



not „ „ 1 Nymphalidae. 



4. Anterior legs of the £ aborted 3 Erycinidae. 



„ „ „ $ developed 5 



5. Anterior tarsi of the $ more or less abbre- 



viated or with one or both claws absent... 4 Lycaenidae. 

 Anterior tarsi normal, claws present 6 



6. Vein 1 a of H.W. present 5 Pieridae. 



„ „ absent 6 Papilionidae. 



