AND ANIMAL LIFE. 387 



2. The second class includes thoracic and abdo- 



minal affections, diseases, and injuries of the 

 spine, and medulla oblongata, which are 

 also classified, from possessing one common 

 influence on the organs of respiration. 



3. Tumours and many anomalous diseases, which 



seem to act directly upon the larger vessels 

 of circulation, constitute the third class. 



CCCXI. The first class is extremely extensive. 

 For the purpose of facilitating description, and of 

 shewing more clearly than I otherwise could the 

 consistency of the classification, it is subdivided 

 as follows : 



a, a small heart. 



b, one or more of its cavities enlarged or dimi- 

 nished in capacity. 



c, diseases of the valves proper to the heart and 

 the great vessels with which it is directly con- 

 nected. 



c?, inflammation. 



e, adhesion of the pericardium. 

 Jl imperfect organization of the heart. 



CCCXII. The heart may be perfectly well 

 formed in relation to itself; its cavities, valves, 

 and parietes, may be proportionate to each other ; 

 yet, as a whole, its relation to the system may 

 be inaccurate, and therefore may predispose to 

 occasional irregularity of action. 



