162 



ANATOMY FOR NURSES 



[Chap. X 



..-•*'? ! 



Fig. 97. — He.^rt in situ (Dalton, in Flint, "On the Heart"), a, b, c, d, e, 

 ribs; 1, 2, 3, 4, 5, intercostal spaces; vertical line, median line; triangle, super- 

 ficial cardiac region ; X on the fourth rib, nipple. 



As placed in the body, it has a very oblique position, and the right 



side is almost in front of 

 the left. 



Myocardium. — The 

 main substance of the 

 heart is composed of mus- 

 cular tissue and is called 

 myocardium. (See page 



m.) 



The arrangement of ,the 

 fibres is very intricate ; 

 they run transversely, 

 longitudinally, obliquely, 

 and in the apex take a 

 spiral turn or twist. Be- 

 tween the muscle fibres is 

 a certain amount of inter- 

 stitial tissue, with nu- 



FiG. 98. — Anterior View of He.*.rt. Dis- meroUS blood-vessels and 



8ECTED, AFTER LONG BoiLING, TO SHOW THE . . 



Superficial Muscular Fibres. (Quain.) lymphatics, and, m SOme 



