INTRODUCTION. 



Tlio shape and size of the liill vary iiieatly, as will be seen by the following 

 illustrations representing fifteen of the principal types among our birds : — 



Bill of Whi/tpooririll 



Bill of' ^ong Sparrow 



...m-- 



^iV 



Bill of Humming-bird 



Bill of Least Bittern 



Bill of Shrike 



Bill vf Vvjck 



BiU of Uerm 



Cere. A moniln-ane (usually hard), whioh covers the base of the upper niandilili'. 



(Hawks, I'airols, .la-gers.) 

 Nasal Fossa, or Nasal Groove, (iroove in wliidi the nostrils open. 

 Qonys. Lower outline (middle) of the under niandilile. A to !'.. 

 Culmen. Tiie ridg«' of the upper niandiltle. 

 Unjjuis. i'lie nail on the end of the upper iiiaiidiiilr. \'erv pimionnceil in some 



families of Water i'.iids, — Ducks, Telicans, and Petrels. 

 riandibles. — Some authors use the woid nKixilhi for the upper half of the bill, ami 



mitiiili/)li\ for the lower. I prefer, however, to de.'^eiiin, the two halves of the bill 



as upi)er and lower nuuidible. 



