xiv INTRODUCTION. 



In order that the descriptions of birds on the succeeding pages may 

 be clearly understood, the figures on Plate 1, with the following ex- 

 planations are given : 



1. Maxilla or upper mandible. 



2. Lower mandible. 



3. Forehead ; also called front and frons. 



4. Iris (Plural irides): Colored circle of the eye around the "dark 



spot" or pupil. 



5. Upper part of throat including chin. 



6. Lower part of throat or foreneck : Jugulum 



7. Breast or pectus, also spoken of as pectoral region. 



8. Wing-coverts (Greater, Middle and Lesser). 



9. Bastard or spurious wing or Alula composed of the feathers grow- 



ing on the so-called thumb. 



10. Occiput ; back part of head. 



11. Tertiaries, Tertials, or tertiary quills are the large inner quills 



that grow from the humerus (arm- bone) or elbow, and in the 

 closed wing are generally concealed by the longer scapular 

 feathers. 



12. Scapulars or scapular feathers. 



13. Abdomen or belly ; under surface of body from breast- bone to 



vent. 



14. Lower tail coverts ; crissum. 



15. Crown or top of head. 



A. Culmen. The ridge of upper mandible. 



B. Cere. The naked skin at base of bill, well shown in Hawks. 



C. Lore or loral space between the bill and eye. 



D. Gape or rictus. 



S. Commissure ; outlines of closed bill. 



The additional technical terms the definitions of some of which 

 are compiled from ^Ridgwatfs Nomenclature of Colors"* sue also 

 employed. 



Ear-covert* rr Auriculars. Feathers covering the ear-opening. Axilla. Arm-pit. 



Alar extent. Measurement of outstretched wings. Apiaries or Axlllars The (generally) soft 



I lengthened feathers growing from the armpit : Adult. This term is applied to individuals 



which have attained full or mature plumage ( " a bird may be adult as regards organization with- 



;ing of adult plumage " ) : Bend of the Wing. Angle or prominence formed at the carpus 



*A | Nomenclature of Colors | for naturalists | and | compendium of useful knowledge | for or- 

 tbologists, | by Robert Ridgway, | curator. Department of Birds, United States National Mu- 

 seum, | with ten colored plates and seven plates of outline illustrations. | Boston: | Little, Brown, 

 and Company. 1 1886. | Price $3.00, 



