Phlebotomy 237 



the apex of the space, the head of the humerus may be obscurely 

 felt. 



The axillary line is the plumb-line descending, from the middle 

 of the first rib, between the axillary folds. In a deep inspiration the 

 chest-wall in front of it moves forwards whilst that behind it moves 

 backwards. 



Superficial veins. The anterior ulnar vein comes from the little 

 finger and the palm of the hand, and, receiving tributaries in its course, 

 is joined in the upper part of the forearm by \\\e posterior ulnar vein, 

 which begins on the back of the little finger as the "vena salvatella. 

 The common ulnar vein which is thus formed is soon joined by the 

 inner division of the median vein to form the basilic. 



The radial vein comes from the back of the hand (where it has 

 large anastomotic arches with the posterior ulnar) and from the thumb ; 

 at the elbow it is joined by the outer division of the median vein to 

 form the cephalic. 



Front of right elbow. (GRAY.) 



The median vein ascends from the palm of the hand, and just before 

 it reaches the bend of the elbow it receives the communicating vein, 

 which brings blood from the venae comites of the radial and ulnar 

 arteries. It then divides into two short trunks, the outer of which joins 

 the radial to form the cephalic, whilst the inner flows into the common 

 ulnar vein to form the basilic. These short trunks are called from 

 their connections median-cephalic and median-basilic respectively. 



Thus, the veins at the bend of the elbow are arranged in the form 

 of the letter M, with all the points prolonged. 



The median-basilic is the vessel at the elbow which is generally 

 chosen for phlebotomy, for the simple reason that it is usually larger 

 than the median cephalic. It has this disadvantage, however, that 

 just beneath it runs the brachial artery ; but, as the bicipital fascia 



