June, '04] ENTOMOLOGICAL NEWS. 181 



which the nomenclature of the Sphingidae is based upon the 

 work of Rothschild and Hartley. We are here asked to forget 

 all our previous associations of names and structure and to 

 learn a totally new combination. Sphinx is no longer typified 

 by species resembling chersis ; it is now applied in the sense in 

 which we have previously used Smerijithiis . Sesia is no longer 

 a clear- wing ; but its representatives are our species of ^llo- 

 pos, — and so on. 



We have heard of discussions concerning the " whichness 

 of the what," or the " thusness of the that," and have consid- 

 ered them as jokes ; but the state of uncertainty at present exist- 

 ing as to our lepidopterological nomenclature is no joke at all. 



The question naturally arises, — what causes all these differ- 

 ences of opinion, and why are such changes necessary ? Before 

 pointing out some of the difficulties, I want to record a little 

 conversation had with one of the authorities in another order, 

 wonderfully familiar with the literature in his own as well as 

 other specialties. He cited a recent work in which the author 

 proves to demonstration that a particular species must be the 

 type of a given genus. There seemed no escape from the con- 

 clusions of the publication until, a little later, another was 

 issued by another author who was equally convincing in his 

 proof that a totally different species was the type of the generic 

 name. 



Of course this aroused interest, and my friend concluded 

 that, as he had all the publications referred to, he would look 

 the matter up himself. He did so, and concluded that neither 

 of the previous writers was correct ; but that an altogether 

 different species must be considered as the type ! Now here 

 we have three authorities, with exactly the same evidence before 

 them, coming to three distinct conclusions ; and each is firmly 

 convinced that he is right. 



How does it happen, then, that so much difference of opinion 

 is possible when the evidence is all before us ? 



When Linnaeus first used his binomial system definitely, in 

 the tenth edition of the Systema Natura, which is accepted as 

 a starting point for our nomenclature, he used the terms Papilio 

 for all butterflies ; Sphinx for all hawk-moths and some other 



