INTRODUCTION. 



The plan of this Key is founded upon the system first ap])iied by a 

 savant named Lamarck to plants ; but it will prove easily workable 

 in all branches of natural history. The idea of dichotomy aims at 

 selecting two contrasted characters. By eliminating that which 

 does not apply to the specimen under notice, and by passing on to 

 the next two characters indicated by the number in the margin, 

 the name is finally reached. 



The system has a fascination of its own which will be readily 

 appreciated after a short acquaintance. 



No previous knowledge of bird life is necessary with this Key, 

 though it might be well to point out the exact meanings of the 

 terms in use : — 



The culmen is the ridge of the upper bill or mandible, and 

 the measurement of this is taken from the feathers at the 

 base to the tip. 

 The tarsus is the shank bone from the middle of the knee to 



the middle of the ankle. 

 The wing is measured from the point of the shoulder to the 



tip of the longest outside feathers or primaries. 

 Wing and tail feathers have all a narrow outer web and a wide 



inner web, which may be differently marked. 

 The lores are the spaces between the eyes and the base of the 



l)ill. 

 The cere is only found in a few genera, and is the membrane 

 bare of feathers at the base of the bill. 

 All other characters will explain themselves. It is essential, 

 however, that they be interpreted strictly as written, not confusing 

 forehead with crown, which is the whole top of the head, nor back 

 w'ith rump, nor breast or flanks with throat or abdomen. But such 

 terms as plumage, upper surface, under surface, and licad have 

 general value only. All measurements, especially those of total 

 length and wing, it must be understood, may vary somewhat with 

 different districts and skins. 



