318 Mr. H. J. Elwes on Modern [Ibis, 



environment has on the colour of plumage, require careful 

 investioation in the liglit of Mr. Bonhote's remarks on sub- 

 species and their part in evolution (Ibis, 1921, p. 270) ; 

 and of Dr. Lowe's still more enlightening paper on " Species 

 and Subspecies' (Ibis, 1922, p. 179). Much better brains 

 than mine, and an amount of study which I cannot give to 

 this very difficult question, are necessary to decide whether 

 it is possible to formulate rules, which can be adhered to by 

 men whose opinions vary, and must always vary, according 

 to the amount of knowledge thej^ acquire, and are capable 

 of using to this end. But we have accumulated evidence 

 that we cannot stop where we are, as, for instance, in the fol- 

 lowing cases : — Mr. Kuroda has, in his recent paper on " The 

 Birds of Tshusima," followed the example of Hartert and 

 his supporters, and has described, on differences of measure- 

 ment in bill and wing, a new subspecies of the Blue Rock- 

 Thrush which already has, according to Kuroda, in the 

 Japanese Empire alone, three described forms, only one of 

 which was recognized by Hartert, on p. G75 of his Catalogue, 

 as Monticola solitarins pliib'pj.wnsis, P. S. L. Miill. ; a name 

 for which he claims priority over manilla Boddaert, though 

 the identification is evidently doubtful. Who is to decide 

 between Hartert and Kuroda ? The latter may well say 

 that he has a better claim to know Japanese birds than 

 Hartert or any European can have, and when Kuroda has 

 exhausted his ambition for subdivision, some younger 

 Japanese ornithologist may spring up desirous for fame, 

 and adopt another view of the position, either by making 

 sevei'al more subspecies, or by uniting them all with our 

 old friend Tardus cyanus, or cf/aneus, of Linnaeus in Ed. xii 

 = T. solitarius of Linnseus in Ed. x. He may upset and 

 unite under one name the nine subspecies of what Kuroda 

 calls Sitt'qxcrus vaiius, into which the Parus varius Tem- 

 minck = sieholdi Seebohm = ruh'idus Blakiston fide 

 Hartert, has been subdivided mainly by Kuroda, on 

 specimens from various islands of the Japanese archipelago ; 

 of these specimens cannot exist in any sufficient lunnber 

 to enable European ornithologists to form an opinion. 



