36 THE STRUCTURE OF THE FOWL 



each muscle is covered by connective tissue, 

 which may be of some density. The contractile, 

 red, fleshy part of a muscle is connected with 

 bones by tendons — sometimes of considerable 

 length, sometimes extremely short. 



By their presence and action, muscles pro- 

 duce marked effect on the surface of the bones 

 to which they are attached or against which 

 they press. Processes, ridges, and grooves 

 on bones are often due to the presence and 

 action of muscles. 



A detailed description of the various muscles 

 of the body would be out of place here ; but 

 to some attention may be directed on account 

 of certain remarkable characteristics. 



The diaphragm of the fowl is rudimentary, 

 and does not form a partition between the 

 thoracic and abdominal cavities as in mammals. 

 The muscle is represented by a tendinous 

 membrane, lying on the ventral surface of the 

 lungs, and certain feeble muscular bundles 

 springing from the ribs. 



In the limbs special muscular arrange- 

 ments are to be expected as a consequence of 

 the modifications necessitated by specialised 

 function. The immense and powerful mass of 

 muscles associated with the pectoral region 



