190 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



geographical range of stragglers seems to widen with the 

 lapse of time. 3. Certain species have greatly increased in 

 recent times over wide districts where they were compara- 

 tively rare. 4. Year by year the raptorial birds of Scotland 

 are becoming fewer. 



lie remarked also that by a comparison ofSibbald's list of 

 birds in "Scotia Illustrata," 1684, with other authorities, he 

 had arrived at the conclusion that most of the larger rapto- 

 rial birds were rapidly disappearing from Scotland, and that 

 even the smaller forms, which were common in the southern 

 and central districts, were yearly becoming rarer. He also 

 expressed his opinion that both the farmer and the game pre- 

 server would lose much when, between them, they succeeded 

 in destroying all the hawks and owls. 12 A, Aug. 24, 333. 



VARIATION OF COLOR IN BIRDS WITH THE LOCALITY. 



The subject of variation of color in birds, as expressing 

 specific distinctions, has for a long time occupied the atten- 

 tion of ornithologists ; and while, with some, the slightest 

 difference in shade was sufficient to establish a separate spe- 

 cies, a wide variation is allowed by others without affecting 

 the idea of specific identity. TVe are gradually, however, 

 coming to appreciate the influence which external conditions, 

 such as light or shade, moisture or dryness, varying tempera- 

 ture, latitude, etc., produce upon color, and so long as the 

 general pattern remains the same we can allow a great vari- 

 ation in tint, and even in size, since, as is well known, this 

 depends largely upon latitude or altitude of birthplace and 

 residence. As a general rule, it may be said that as we go 

 southward from a north-temperate latitude, with the increas- 

 ing temperature and brighter sky the colors are deeper and 

 the size less ; and, on the other hand, in proceeding northward 

 and into more clouded atmospheres, the dimensions become 

 greater, with a decrease in general brilliancy. In sandy or 

 barren regions the accompanying birds become of a grayish 

 tint, while in red soils a reddish shade will be appreciable. 



Again, in certain regions, the birds exhibit a tendency to 

 melanism, or a blackening, this being noticeable in Florida, 

 and more especially in the West India Islands, as compared 

 with the United States. An instance of this is seen in the 

 common red-winged blackbird, the female of which, as found 



