PRACTICAL ORNITHOLOGY. 



FIFTH LESSON. 



SUBURBAN EXCURSION. NOTES ON BIRDS AND OTHER BIPEDS. VITAL FUNC- 

 TIONS OF THE FORMER. ORGANS OF RESPIRATION AND VOICE. LUNGS. 

 AIR-CELLS DISTRIBUTED THROUGH THE BODY. CHANGES OPERATED ON 

 THE BLOOD BY RESPIRATION. TRACHEA AND BRONCHL LUNGS. RES- 

 PIRATORY AND VOCAL ORGANS OF THE ROOK AND BLACKBIRD DESCRIBED 

 IN DETAIL: LARYNX AND ITS MUSCLES; SYRINX, ITS STRUCTURE AND 

 MUSCLES. TRACHEA OF THE BROWN LINNET, BROWN PTARMIGAN, WOOD 

 PIGEON, AND PARROTS. TUBE OF THE TRACHEA, ITS RINGS, AND THE 

 MECHANISM BY WHICH THEY ARE MADE TO SLIP BEHIND EACH OTHER. 



, To the practical ornithologist all seasons are welcome. Even 

 " the dreary month of November "" brings gladness, for it in- 

 creases his capacity for labour, and renders protracted vigils 

 less injm'ious to health. Besides, the birds which in summer 

 were dispersed over the country, and hidden among woods and 

 thickets, now approach the dwellings of men, and are easily 

 traced among the leafless twigs. Over the fields too, and upon 

 the estuaries and rivers, are scattered many species which have 

 been driven southward by the severity of the weather, and which 

 can be obtained only at this season. Now is the time for dis- 

 section, without which our practical ornithology would fail to 

 make us acquainted with the harmonies of nature. 



The beams of the morning sun, unable to penetrate the thick 

 mist that is spread over the ocean, merely tinge the eastern sky 

 with dim red ; the ground is hardened by the frost, and the 

 grass crusted with delicate crystals of feathery snow. Most of 

 the Blackbirds and Thrushes are in the gardens, whither we 

 cannot follow them ; but many will be found under the hedges, 

 especially in the neighbourhood of farm-houses and villages. 

 There has been little hard weather as yet, and they are fat and 

 full of sap, for they have feasted luxuriously on the snails which 

 they have jerked from their winter-quarters in the walls and 

 hedge-banks. 



VOL. II. B 



