342 



MUSCLES OF THE ABDOMINAL CAVITY. 



down the perineum, to assist in contracting the mouth of the 



Levator Ani, 



Arises, as in the male, within the pelvis, and descends along 

 the inferior part of the vagina and rectum. 



Inserted into the perineum^ sphincter ani, extremity of the 

 vagina and rectum. 



Use. To raise the extremity of the rectum upwards, to 

 contract the inferior part of the rectum, and to assist in con- 

 tracting and supporting the vagina ; and, perhaps, by pressing 

 on the veins, to contribute to the distention of the cells of the 

 clitoris and corpus cavernosum of the vagina. 



Muscles situated within the Cavity of the Abdomen. 



Fig. 88.* 



These consist of a single 

 muscle, and four pair. 



Diaphragma. 

 This broad thin muscle, 

 " which makes a complete 

 septum between the tho- 

 c rax and abdomen, is con- 

 cave below and convex 

 above ; the middle of it on 

 each side reaching as high 

 within the thorax of the 

 skeleton as the fourth rib : 

 it is commonly divided 

 into two portions. 

 1. The superior or, 



Greater Muscle of the Dia- 

 phragm. 

 Arises, by distinct fleshy 



* Thorax of a male. On the left side the muscles are removed ; on the right 

 ihey are left in situ, a, a, Cervical and lumbar parts of the spinal column, the 

 dorsal portion is concealed by the sternum, b. c, c, The true ribs, c', The false 

 ribs, d, The clavicle, e, Intercostal muscles. /, Last false rib, concealed by 

 the origin of a part of the greater muscle of the diaphragm, g, The arch 



