1881.] OF AMURLAND, NORTH CHINA, AND JAPAN. 861 



them, without attempting to study the generic affinities of the 

 species, as this would be a work beyond my time or power. With 

 respect to the species described by old authors, I have also as a 

 rule accepted the verifications of previous writers, believing that 

 when a species is well known under any name it is better to adhere 

 to it than, for the sake of a few years' priority, to make a change, 

 founded as such changes must often be on very doubtful identifi- 

 cations of descriptions. In many genera, such as Golias, Argynnis, 

 or Lycana, the best descriptions by modern authors are of very little 

 use in making out doubtful species ; how much inore, then, must it be 

 the case when old authors are referred to. Only good figures or the 

 examination of the type specimens can really be depended on ; and 

 even then doubts will often crop up as to what the insects are. For 

 instance, who could follow Mr. Butler's descriptions of species of Terias 

 in the Trans. Ent. Soc. 1880, p. 198, without the plates? and who 

 could form an opinion of the species of Japanese CoUas from descrip- 

 tions, however elaborate, of such species as C. ehoesi, C. pallens, or 

 C. subaurata 1 "With regard to the species included in Staudiuger's 

 Catalogue, I have adopted his nomenclature, as I believe that it is as 

 nearly accurate as such a work can possibly be made, and it is 

 generally adopted by European lepidopterists. There must be 

 numerous errors in my work, especially as regards the Hesperidse, 

 inseparable from a paper which cannot be written at home with the 

 whole of the specimens before one, but must be put together from 

 notes often taken under circumstances unfavourable to accuracy. For 

 these errors and for errors of judgment I beg the indulgence of those 

 who may have occasion to refer to my work ; and I assure them, 

 that if any of my conclusions are faulty, as undoubtedly some must 

 be, I have endeavoured to put together the scattered materials at my 

 disposal with a regard for scientific truth only, and not with any 

 wish to throw discredit on the observations of others. Finally, I 

 must express my thanks to Mr. Godman and Dr. Staudinger for the 

 great facilities which they have given me in examining their collec- 

 tions (from every point of view the two best in the world), and to 

 Messrs. Kirby and Butler, of the British Museum, whose time I have 

 so often taken up in a manner which I think most unreasonable, but 

 which under the present regulations of the Museum is unavoidable. 



On making an analysis of the distribution of the species I get the 

 following results, which, though they must be considered as aj)proxi- 

 mate only, will, I believe, give a very fair idea of the character of the 

 Butterflies in each country. 



Amurland. 

 Species common to and characteristic of the Palsearctic region 85 

 Peculiar to the Eastern part of this region, but mostly of 



Palaearctic genera 80 



Belonging to genera characteristic of the Indian region, or 



cosmopolitan in Old World . . 10 



Common to Amurland and Japan, 78. 175 



