INTRODUCTION. 



R shows on the bill the culmen, or crown, of the 

 upper mandible. 



S is the naked skin at the base of the bill, 



called the cere. 

 T shows the position of the lores between the V --' 



eye and bill. 

 U indicates the gape, the angle at the junction of the upper and lower 



mandibles : the feathers in this locality are called rictal. 

 V is the commissure, or the folding edges of the mandibles. 



In addition to these parts, there are the flanks or sides 

 of the bird ; the pectus, or breast ; the flexure, or bend of 

 the wing ; the iris, or irides, the colored circle which sur- 

 rounds the pupil of the eye ; and the toes and tibia : the 

 former are sometimes palmated, as with the swimmers, or 

 natatores ; and the latter is that portion next above the 

 tarsus on the leg. 



