210 



THE DOG IN DISEASE. 



ventilation of the blood pass, and extends from the nos- 

 trils to the air-cells. 



Briefly, the tract consists of a mucous membrane cov- 

 ered with epithelial cells, abounding in blood-vessels and lin- 



FIG. 12. LUNGS, ANTERIOR VIEW (SAPPEY). 



1, upper lobe of left lung ; 2, lower lobe ; 3, fissure ; 4, notch corresponding to 

 apex of heart : 5, pericardium ; 6, upper lobe of right lung ; 7, middle lobe ; 

 8, lower lobe ; 9, fissure ; 10, fissure ; 11. diaphragm ; 12, anterior mediasti- 

 num ; 13. thyroid gland ; 14, middle cervical aponeurosis ; 15, process of at- 

 tachment of mediastinum to pericardium ; 16, 16, seventh ribs ; 17, 17, trans- 

 versales muscles ; 18, linea alba. Though this cut refers to the human sub- 

 ject, the relations of parts are substantially the same in the dog. 



ing the nose, back of the throat, the voice box (larynx), the 

 wind-pipe (trachea), its subdivisions (bronchi), and blend- 



