TEOG 237 



principal vessels are found after death to be plain- 

 ly visible on account of the accumulation of blood 

 in them. 



Tlie external anatomy of the heart. 

 What is its position vp^ith regard to the sternum ? 

 Can you give any reasons for this? What is the 

 position of the heart with reference to the liver? 

 The lungs ? ^Notice the membranous sac or peri- 

 cardium, which surrounds the heart. What is its 

 texture? Color? Does it fit closely around the 

 heart? Cut open the tip of the pericardium and 

 note the contained fluid, the pericardial fluid. 

 What is its color ? Is it abundant ? Split open 

 and remove the pericardium. At what point is it 

 attached to the heart ? Is it attached to any other 

 organs? What is the shape of the heart? Length? 

 Breadth? What variations in color in different 

 parts? Notice the light-colored apex, the ven- 

 tricle. Towards which end of the body is the 

 apex of the heart directed ? How much of the 

 entire heart does the ventricle form? At the 

 left (really right) side of the base of the ven- 

 tricle, as you look at it, find a short, light-colored 

 tube, the truncus arteriosus, which at its ante- 

 rior end divides into two branches, the aortic 

 arches. On each side of the truncus is seen an 

 auricle. How much of the heart do the auricles 

 form? How do they differ in color, shape, and 

 size, from the ventricle ? With the tip of the for- 

 ceps carefully press the wall of one of the auri- 

 cles. How does it compare in firmness with that 

 of the ventricle ? What is the shape of the trun- 

 cus ? How long is it ? What is its diameter ? In 



