114 APPENDIX 



9 is the sign used to indicate the female sex. 



A subspecies is a geographical race, modified in size, color, or 

 proportions chiefly by the influence of climate. These varia- 

 tions are especially marked in non-migratory birds of wide dis- 

 tribution, subject, therefore, to climatic extremes. The Downy 

 and the Hairy Woodpeckers, for example, are split up into 

 numerous races. It should be remembered that when a species 

 has been separated into races, or subspecies, all the subspe- 

 cies are of equal rank, even though they are differently 

 designated. The one originally discovered and first described 

 bears the old Latin name which consisted of two words, while 

 the new ones are designated by triple Latin names the old 

 binomial and a new name in addition. The binomial indicates 

 the form first described. The forms designated by trinomials 

 may be equally well known, abundant, and widely distributed. 

 For example, among the woodpeckers, the northern form of 

 the Hairy Woodpecker was first discovered and bears the 

 name Dry abates villosus ; but the first Downy Woodpecker de- 

 scribed was a southern bird, and the northern form was not 

 separated until a few years ago, so that the southern bird is 

 the type, and the northern one bears the trinomial, Dryobates 

 pubescens medianus. 



North America, by the decision of the American Ornitholo- 

 gists' Union, is held to include the continent north of the pre- 

 sent boundary between Mexico and the United States, with 

 Greenland, the peninsula of Lower California, and the islands 

 adjacent naturally belonging to the same. 



The following key and descriptions will enable the student to 

 identify any woodpecker known to occur within these limits : 



A. KEY TO THE WOODPECKERS OP NORTH AMERICA. 



Family characteristics : color always striking, usually in spots, 

 bars, or patches of contrasting colors, especially black and white, 

 Sexes usually unlike; male always with some portion of red or 

 yellow about head, throat, or neck. Tails stiff, rounded, com- 

 posed of ten fully developed pointed feathers (and two undevel- 

 oped feathers). Wings large, rounded, with long, conspicuous 

 secondaries, and short coverts. Bill straight, stout, of medium 



