394 MUSCLES. 



that the round ligament of the uterus supplies the place of the 

 spermatic chord, and there is no cremaster muscle.* 



SECT. III. MUSCLES OF THE UPPER AND POSTERIOR PARIETES OF THE 



ABDOMEN. 



These muscles are constituted by a single symmetrical one, 

 and by four pairs : they can only be seen advantageously by 

 removing the abdominal viscera. 



1. The Diaphragm, (Diaphragma,) 



Is a complete, though moveable septum, placed between the 

 thoracic and abdominal cavities; it is extremely concave be- 

 low and convex above, the concavity being occupied by seve- 

 ral of the abdominal viscera. It is in contact above with the 

 pericardium and lungs, and below with the liver, spleen, and 

 stomach. 



It is connected with the inferior margin of the thorax on all 

 sides, and has for its centre a silvery tendon, resembling in its 

 outline the heart of a playing card. This cordiform tendon 

 occupies a considerable part of the extent of the diaphragm, 

 has its apex next to the sternum, and its notch towards the 

 spine ; and the muscular part of the diaphragm is inserted all 

 around into its circumference. The cordiform tendon is nearly 

 horizontal in the erect posture, its elevation being on a line 

 with the lowest end of the second bone of the sternum. On 

 each side of this tendon some of the muscular fibres rise so high 

 upwards before they join it, that they are on a horizontal level 

 with the anterior end of the fourth rib. The fasciculi of mus- 

 cular fibres are, for the most part, convergent from the cir- 

 cumference of the thorax, and are easily separated from one 

 another. 



In the diaphragm are three remarkable foramina. The first 

 (the Foramen CEsophageum) is in the back of the muscle, be- 



* For an account of both Inguinal and Femoral Hernia, the reader is referred 

 to Lessons in Practical Anatomy, 2d Edition. Philadelphia, 1836. 



