m>7.] 



AN ATTEMPT TO ELUCIDATE AND TO FIX THE TYPES OF 



TORTRIX, TINEA and ALUCITA, 

 THREE OF THE LINN.EAN SUBDIVISIONS OF PEAL/ENA, L. 



BY THE RIGHT HON. LORD WALSINGHAM, MA., LL.D., F.R S., 



AND 



JOHN HARTLEY DURRANT, F.E.S., Memb. Soc. Ent. de France. 



As Professor Grote has recently on more than one occasion con- 

 fessed his inability to determine the types of these subdivisions, and 

 as one of them seems to be used incorrectly, no apology is necessary 

 for publishing the conclusions arrived at after careful study extending 

 over several years, especially as it is hoped that the results obtained 

 will have the merit of finality, being based on a stricb application of 

 the Law of Priority. The elucidation of these Linnsean subdivisions 

 is attended with unusual difficulty, not only on account of the loose 

 and illogical manner in which some of them have bepn treated by 

 writers subsequent to Linnssus, but also because at the outset we have 

 to face the much debated question whether these subdivisions can be 

 accepted as genera attributable to Linnaeus himself. 



It is usually considered that Linnaeus w^as the originator of that 

 binomial system which is in use at the present day, and so far as the 

 special name is concerned this assumption is certainly correct, but in 

 the Lepidoptera (to which all these remarks apply exclusiuely') Linnaeus 

 cannot be said to have described a single genus — his assemblages of 

 species under a distinctive heading are of not less ordinal value than 

 the groups which are now called Families, and therefore the sub- 

 divisions of these heterotypical assemblages more nearly approximate 

 what we now call a genus. From a modern point of view the so-called 

 genera as well as their subdivisions are for the most part of no sys- 

 tematic value, and it is only the fact that these names obtained priority 

 for groups of species whose sole claim to recognition rests in the 

 restrictions made and the definitions applied to them by subsequent 

 writers that renders it necessary to discuss them all. 



If we regard the Linnaean names Papilio, Sphinx and Phalcena 

 as genera, then it is obvious that those designations which were used 

 in plural form in subdividing these three large assemblages were not 

 considered as of equal value with the whole group of which they were 

 component parts. Though confining this enquiry to three only of the 

 subdivisions of Phalcena, the same arguments apply equally to the 

 other trinomial subdivisions proposed by Linnaeus. 



It is certain that Linnaeus did not consider these subdivisions as 

 genera, for they are not numbered, whereas all the Linnaean genera 



