146 ALLEN'S NATURALIST'S LIBRARY. 



genus Parus the wing is longer than the tail. It is a Palnenrctic 

 genus, and the uniting of the Himalayan genus ^Egithaliscus with 

 sEgithalus seems to us to be a great mistake, as from the 

 measurements given by Dr. Gadow himself in the British 

 Museum " Catalogue of Birds," the wing and tail are evidently 

 equal in length in sEgithaliscus. The range of the genus 

 ALgithalus may, therefore, be said to extend over Europe, and 

 eastwards through Siberia to the Pacific and to the Japanese 

 islands. It is a very curious fact, often remarked upon by ornitho- 

 logists, that in Japan, so far away from Great Britain, there re- 

 occur certain striking elements of the British Avi-fauna. Many 

 species are precisely the same, others are closely allied and re- 

 presentative. Thus our English Siskin and Brambling are 

 found in Japan, while our Greenfinch is replaced by a closely 

 allied form. Our Hawfinch is scarcely distinguishable from the 

 bird of the Japanese islands, and in the case of the Long- 

 tailed Tit, the Japanese species, sEgithalus trivirgatus, is more 

 like its British ally, ^E. vagans, than the white-headed form, /E. 

 caudatus, which is the species of the intervening area from 

 Scandinavia to Eastern Siberia, though Mr. Seebohm recog- 

 nises a Siberian form, s. macrurus. 



&. vagans, the British species, was at first supposed to be 

 confined to Great Britain, but it certainly extends over France 

 and into Northern Italy, to judge by the specimens in the 

 British Museum, but little really is known of its distribution. 

 In the Rhine Provinces of Germany, Count von Berlepsch 

 has found a form which he pronounces to be intermediate 

 between AL. vagans and ^E. caudatus of Northern Europe. He 

 has very kindly sent several specimens to the Museum, and 

 we must say that we are not yet convinced of the intergrada- 

 tion of the two races. The young of both are indistinguishable, 

 and have a black band on each side of the crown. In adult 

 /E. caudatus this entirely disappears, and the head becomes 

 snow-white, while in AL. vagans the black band becomes per- 

 manent in the adults, and is one of the features of the species. 

 The specimens which are considered to be intermediate be- 

 tween the two forms have a white head with more or less 

 remains of a lateral stripe on the crown. This may very well 

 be the remains of the immature plumage, and does not neces- 

 sarily afford evidence of interbreeding or even of the imperfect 



