A First Glance at the Birds, 



continent might separate the birds of 

 the rainy coast district of Humboldt 

 County from the species inhabiting the 

 arid region of the Colorado Desert, so 

 different are they in form, plumage and 

 habits. 



I am often asked whether the birds 

 of California differ much from those of 

 New England, and the comparison is a 

 most interesting one to make. In order 

 to understand the distinctions, however, 

 it will be necessary to explain the differ- 

 ence between a species and a variety or 

 geographical race. Two related birds 

 are said to be distinct species when they 

 possess any constant marks of differ- 

 ence, however slight these may appear 

 to the untrained eye. When connect- 

 ing links are found between two allied 

 forms they are said to intergrade and 

 one is considered a mere variety of the 

 other. For example, the western robin 

 differs from its eastern prototype by a 

 few very trivial characters, which com- 

 pletely blend in the region intermediate 



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