40 



KEY AND DESCRIPTION 



the great variations for age. The whole description should be 

 read before deciding. The measurements of parts are very 

 imjwrtant and should always be noted. Generally these meas- 

 urements are only average ones, and some differences may 

 be allowed for. In order to judge of the amount to allow, 

 notice the extent of the variation in the length of the wing 

 as given in parenthesis. Other parts var}- in about the same 

 proportion. Dimensions are always given in inches and such 



fractions thereof as are found on all common rulers. The 

 '' length" of the bird is the distance from the tip of bill with 

 the neck extended to the end of the longest tail feather. In 

 mounted birds, allowance must be made for the curved neck. 

 The "jfHif/" is the straight distance from the bend of the 

 wing to the tip of the longest primary. This can always be 

 accurately determined from any specimen ; and so throughout 

 the book, in both keys and descriptions, great use is made 

 of this measurement. The " tail " is the length of the long- 



