The Birds' Calendar 



ing al)oiit seven inches long, and the Bohemian 

 about eight), and with a shghtly different tinge 

 of brown, it is scarcely distinguishable from the 

 cedar-bird. 



It is very common for any type of bird to 

 have distinct varieties in north and south, and 

 often in east and west. Thus among the more 

 familiar birds we find a northern and a southern 

 variety of the chickadee, the wren, the shrike, 

 and the nuthatch, although the range of the two 

 nuthatches differs less. East and west also have 

 their counterparts in sparrows, bluebirds, robins, 

 and many others. The western robin much re- 

 sembles the eastern, but has a black band across 

 the breast. In these cases the difference seems 

 to be more in plumage than in habits. It will 

 be one of the most interesting discoveries in re- 

 gard to birds when we learn the causes that 

 differentiate a genus into its species, causes 

 which it is to be presumed are of the same nat- 

 ure, though not on so broad a scale, as those 

 which from the original ty[)e of bird have pro- 

 duced classes, orders, families, and genera. 



The vocal powers of the cedar-bird are very 

 limited, as it can produce only a faint whistle 

 or lisp, much like a note sometimes produced 

 by the robin, but not so iisthmatic. 

 64 



