228 ZOOLOGICAL GEOGRAPHY. [papt m 



Colcoptera. — The beetles of Japan decidedly exhibit a mixture 

 of tropical forms with others truly Pahearctic, and it has been 

 with some naturalists a matter of doubt whether the southern and 

 best known portion of the islands should not be joined to the 

 Oriental region. An important addition to our knowledge of 

 tlie insects of this country has recently been made by Mr. George 

 Lewis, and a portion of his collections have been described by 

 various entomologists in the Transactions of the Entomological 

 Society of London. As the question is one of considerable in- 

 terest we shall give a summary of the results fairly deducible 

 from what is now known of the entomology of Japan ; and it 

 must, be remembered tliat almost all our collections come from 

 the southern districts, in what is almost a sub-tropical climate; 

 so that if we find a considerable proportion of Pahearctic forms, 

 we may be pretty sure that the preponderance will be much 

 greater a little further north. 



Of Carabidse Mr. Bates enumerates 244 species belonging to 

 84 genera, and by comparing these with the Coleoptera of a 

 tract of about equal extent in western Europe, he concludes that 

 there is little similarity, and that the cases of af&nity to the forms 

 of eastern tropical Asia preponderate. By comparing his genera 

 with the distributions as given in Gemminger and Harold's 

 Catalogue, a somewhat different result is arrived at. Leaving 

 out the generic types altogether peculiar to Japan, and also those 

 genera of such world-wide distribution that they afford no clear 

 indications for our purpose, it appears that no less than twenty - 

 two genera, containing seventy-four of the Japanese species, aie 

 either exclusively Pala;arctic, Pahearctic and Nearctic, or highly 

 characteristic of the Pahearctic region ; then come thirteen genera 

 containing eighty-seven of the species which have a very wide 

 distribution, but are also Paltearctic : we next have seventeen 

 genera containing twenty-four of the Japanese species which are 

 decidedly Oriental and tropical. Here then the fair comparison 

 is between the twenty-two genera and seventy-four species whose 

 affinities are clearly Pahearctic or at least north temperate, and 

 seventeen genera with twenty-four species which are Asiatic 

 and tropical ; and this seems to prove that, although South 



