78 



STRUCTURE AND COMPARISON. 



those that lie along the upper arm-bone are the tertiaries, or 

 scapulars, as they are sometimes called, that is, shoulder 

 feathers. The primaries are always either nine or ten in 

 number, and never vary in birds of the same family ; they are 

 also unevenly webbed and often have the broader web sheared 



HG FEDCB A 



FIG. 16. DIAGRAM OF TECHNICAL TERMS. 



A Primaries. B Secondaries. C Primary Coverts. D Greater Coverts. 

 E Tertiaries. F Throat. G Chin. H Bill. / Front. J Crown. 

 K Lesser Coverts. L Interscapular region. M Leg (tarsus). N 

 Abdomen. Rump. P Upper tail coverts. Q Under tail coverts. 



away toward the tip, making emarginate primaries. The second- 

 aries vary much in number, are evenly webbed or nearly so, 

 are never emarginate, and differ from the primaries in one 

 other important respect, they are movable. 



With the bird's wing in our hand we should notice one other 



