178 Anatomy Applied to Medicine and Surgery. 



last -rib, assists forced expiration and, when one muscle 

 acts from above, it raises the pelvis toward that side, but, 

 when both act, they flex the trunk when it is extended, 

 and extend it, when already flexed. The psoas and iliacus 

 acting from above, flex the femur, at the same time, rota- 

 ting it outwards ; from below, they flex the body and also 

 assist in maintaining the upright position. The psoas 

 parvus is a tensor of the iliac fascia. 



Landmarks of abdominal parietes. Nerves. 

 Brewer, of New York, gives, as the result of a number of 

 examinations undertaken for the purpose of ascertaining 

 the course of the lower intercostal nerves, the following 

 landmarks : The seventh intercostal supplies the neighbor- 

 hood of the ensiform cartilage. To represent the eighth 

 nerve, draw a line from a point immediately below the 

 junction of the eighth costal cartilage with the seventh, 

 upwards towards the sternum. This nerve supplies the 

 "pit"of the stomach. A line drawn from a point just be- 

 low the junction of the ninth rib with its cartilage, hori- 

 zontally towards the median line, will correspond to the 

 ninth nerve. The tenth may be represented by a line 

 drawn from a point half an inch above the tip of the 

 eleventh rib towards the anterior superior spinous process 

 of the opposite ilium, and crossing, therefore, the median 

 line about the level of the umbilicus. For the eleventh, 

 draw a line from a point half an inch below the tip of the 

 eleventh rib, towards the middle of the opposite Poupart's 

 ligament, and for the twelfth, one drawn from a point half 

 an inch below the tip of the twelfth rib, towards the spine 

 of the pubes of the opposite side. The rest of the lower 

 part of the inguinal region would be supplied by the ilio- 

 hypo gastric emerging about one and a half inches above 

 the external abdominal ring, while the ilio-inguinal would 

 supply a very small area beneath its point of emergence 

 from the external ring. 



