6 HOW BIRDS ARE NAMED 



that every bird he sees has a name, and in the preceding section having 

 suggested ways in which this name may be learned, the somewhat 

 obscure details of nomenclature may be made clearer by explaining 

 how the bird got it. In doing so I draw freely from a similar effort in 

 the "Color Key to North American Birds." 



Birds have two kinds of names. One is a common, vernacular or 

 popular name; the other is a technical or scientific name. The first 

 is usually given to the living bird by the people of the country it in- 

 habits. The second is applied to specimens of birds by ornithologists 

 who classify them. Common names in their origin and use know no 

 law. Technical names are bestowed under the system of binomial 

 nomenclature established by Linnaeus in 1758, and their formation 

 and adoption are governed by certain definite, generally accepted rules. 

 The Linngean system, as it is now employed by most ornithologists, 

 provides that a bird, in addition to being grouped in a certain Order, 

 Family, etc., shall have a generic, a specific, and, often, a subspecific 

 name which, together, shall not be applied to any other animal. 



Generally speaking, Orders and Families are based on skeletal, 

 muscular, and visceral, "or what may be termed internal characters; 

 while genera are based on the form of bill, wings, feet and tail, and 

 sometimes on pattern of markings, and species and subspecies on color 

 and size, or external characters. Thus, all the members of an Order 

 agree in major internal characters; those of a Family further agree in 

 minor internal characters; those of a Genus, in addition, resemble one 

 another in external characters, while species and subspecies differ only 

 in color and in size. 



Frequently it happens that a bird may possess some of the char- 

 acters of one group in connection with some of the characters of another 

 group, and such birds, collectively, create intergrading groups known 

 as Suborders, Subfamilies, Subgenera, or Subspecies. With the last, 

 the student is especially concerned since they figure in the name by 

 which a bird is known. 



In pre-Darwinian days it was generally believed that a species was 

 a distinct creation whose characters did not vary from a certain type. 

 But in later years comparison of many specimens of a species from 

 throughout the region it inhabits, shows that specimens from one part 

 of a bird's range may differ in size and color, or both, from those taken 

 in another part of its range. At intervening localities, however, inter- 

 mediate specimens will be found connecting the extremes. (See beyond, 

 under Color and Climate.). 



Variations of this kind are termed geographic, racial or subspecific 

 and the birds exhibiting them are known as subspecies. In naming 

 them, a third name, or trinomial is employed, and the possession of 

 such a name indicates, at once, that the bird is a geographic or racial 

 representative of a species with one or more representatives of which 

 it intergrades. 



In illustration let us now trace the history of a trinominal designa- 



