'344 ORNITHOLOGICAL EXPLORATIONS. 



of the white color must be erroneous. Nor can ii be the northerly posi. 

 tion, for these white forms are found at 53° north latitude. The pecu- 

 liarities of a continental climate will not suffice for an explanation, 

 since Kamtschatka is a peninsula surrounded by great sheets of water 

 on nearly all sides. 



It may be well to remark that this increase of white is not in the 

 nature of a bleaching or fading of the darker color. They are simply 

 replaced by pure white, and the parts of the body which in the allied 

 forms are white have this color still purer and more dazzling in the 

 Kamtschatkan forms. In the same manner the other colors seem to be 

 purer and, in many instances at least, to be more intense also. The 

 color which seems to suffer most reduction is the black one, but, as re- 

 marked, it is only in extent, not in intensity. Without offering any 

 theory for the solution of the question, at present, I would only call 

 attention to the fact that, while the black color of the feathers is due 

 to a pigment, the white color is not, it being caused by the accumula- 

 tion of colorless air-filled cells. In respect to the changes within the 

 individual feathers we know as yet next to nothing^ and not until it has 

 been ascertained what are the causes and the nature of the changes in 

 the individual feather, can a trustworthy theory be advanced concern- 

 ing the modifications of the color in the species generally. 



As already indicated, the rest of the resident species are widely dis- 

 tributed Gircumpolar and North-Palsearctic forms which consequently 

 occur in the neighboring countries as well, and therefore are of little 

 interest in the present connection. A few words only need be said 

 about three of these species. The Raven of Kamtschatka has been 

 separated as peculiar under the name of Corvus corax lamischaticus. 

 Not having seen specimens we are unable to appreciate the alleged dif- 

 ferences from the common stock. This may be our fault, or that of the 

 description, but we should not be surprised if the race ultimately should 

 prove to be valid, and only remark that the Raven has not yet been 

 found in Japan proper, specimens having only been obtained in the 

 Kuril Islands. The other species worthy of a few remarks is Leuco- 

 sticte hrunneomicha. A bird which has been called by that name is well 

 known from Japan, and the National Museum possesses specimens from 

 Vladivostok, on the Asiatic mainland, on the opposite side of the Japan 

 Sea. It is reported from the Kuril Islands, and also from the eastern 

 coast of the Kamtschatkan Peninsula. The genus Leucosticte is Asiatic 

 and American in its distribution, and most of the si)ecies show a great 



