DIRECTOKY TO BIKDS OF EASTERN NORTH AMERICA. O 



EXPLANATION OF DIAGRAM OF CHIPPING SPARROW. 



A, External Parts:- 1, bill; 2, forehead; 3, crown; 

 4, occiput; 5, nape; 6, hind neck; 7, back; 8, wing; 9, up- 

 per tail coverts ; 10, under tail coverts; 11, tibia; 12, abdo- 

 men; 13, belly; 14, breast; 15, throat; 16, ch.in ; 17, supercil- 

 iary region; 18, lores; 19, ear coverts; 20, maxillary region ; 

 22, tarsus; 32, hind toe; 42, front toe; 52, tail. 



Internal, Parts:- a, tongue; b, larynx; p, syrinx; c, 

 windpipe; e, sterno trachealis ; f, bronchial tube; G g, gul- 

 let ; H, crop; K, stomach; j, proventriculus-, l, fold of duo- 

 denum; M, pancreas; o, vent; d, ovaries; q, vertebrae of 

 neck; r, vertebrae of back; s, tail bones; t, heart; n, lungs; 

 V, keel ; i m, liver. 



B, Wing OF Chipping Sparrow:- 1, lesser coverts; 2^ 

 middle coverts; 3, greater coverts; 4, spurious wing; 5, pri- 

 maries ; 6, secondaries. 



C, Bill OF Cardinal Grosbeak:- a, upper mandible ; 

 B, lower mandible; d, nostril. 



