14 



SCIENCE PRIMERS, 



[§n. 



directly. The round flat body of each vertebra is 



.\ I » 



Fig. 2. 



A, a diagrammatic view of the human body cut in half lengthways. 

 C.S. the cavity of the brain and spinal cord ; iV, that of the nose ; M^ that 

 of the mouth ; Al. Al. the alimentary canal represented as a simple straight 

 tube ; //, the heart ; Z>, the diaphragm. 



B, a transverse vertical section of the head taken along the line ab ; 

 letters as before. 



C, a transverse sectioa taken along the line c d; letters as before. 



