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Tne Development or tne Coelomic Cavities 



A. Introduction 



1. Definitions 



2. Origin of the primitive splanchnocoelic coelom 



B. Early divisions of the primitive splanchnocoelic coelom 



1. Formation of primitive suspensory structures 



2. Formation of the primitive transverse division of the body and the primary peri- 

 cardial and peritoneal divisions of the coelom 



a. Lateral mesocardia 



b. Formation of the liver-septum transversum complex 



1) Formation of the liver-septum complex through modification of the ventral 

 mesentery by liver outgrowth 



2) Formation of the liver-septum complex in the human embryo 



c. Formation of the primary septum transversum 



C. Coelomic changes in fishes, amphibians, reptiles, and birds 



1. In fishes 



2. In amphibians, reptiles, and birds 



D. Formation of the coelomic cavities in mammals 



1. Formation of the pleuropericardial membrane 



2. Development of the pleuroperitoneal membrane 



E. Development of independent pericardial walls 



1. The arrangement of the parietal pericardial wall in fishes 



2. Formation of an independent parietal pericardial wall in the chick 



3. Formation of the independent parietal pericardial wall in amphibians and reptiles 



4. Separation of the parietal pericardial wall in mammals 



F. The mammalian diaphragm 



G. The pulmonary diaphragm or aponeurosis of the chick 

 H. The omental bursa 



I. The formation of various ligaments in the stomach-liver region 



1. The gastro-hepatic .and hepato-duodenal ligaments 



2. The coronary ligament of the liver 



3. The falciform ligament of the liver 



4. The gastro-splenic ligament 



A. Introduction 



1. Definitions 

 The coelomic cavities are the spaces which come to surround the various 

 viscera of the body such as the pericardial cavity around the heart, the pleural 



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