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posterior wall of the cardiac region of the fore-gut. It 

 is attached at each side to the posterior border of the 

 infero-lateral cardiac ossicle. 



Anterior Cardiac Muscle (c.ant.}. This is a median 

 muscle extending as a broad and thin sheet down the 

 front wall of the fore-gut. It arises in the median line 

 on the front of the mesocardiac ossicle and passes 

 forwards. As it passes downwards along the front wall 

 of the fore-gut it divides into two main branches, which 

 are attached separately to the front wall of the fore-gut. 



The above muscle must not be confused with the 

 muscle of the same name described by Mocquard. The 

 latter muscle is on the antero-lateral wall. I therefore 

 designate it the Antero-lateral Cardiac Muscle (c.al.}. 

 There is one pair of these muscles, each being situated on 

 the antero-lateral wall of the fore-gut immediately above 

 the oesophagus. It is attached to the anterior border of 

 the membranous antero-lateral cardiac plate, and passes 

 upwards almost to the median line. 



The above two sets of muscles act as constrictors of 

 the cardiac portion of the fore-gut. 



Circular Oesophageal Muscles (c.oe.}. These are 

 present as a broad band running around the oesophagus 

 and acting as constrictors of the oesophagus. 



Lateral Pyloric Muscles (py.lat.}. There are several 

 pairs of muscles some broad and others very small 

 arising at each side from the upper part of the post- 

 pectineal ossicle and the infero-lateral cardiac ossicle. 

 They pass upwards and are inserted on the various 

 ossicles of the lateral and dorsal walls of the pyloric 

 region of the fore-gut. These muscles serve as constrictors 

 of this region of the fore-gut. 



