Congenital Anomalies of Arteries and Veins 19 



A. Thoracalis Siiprema 



This was present in 90 per cent, of my series and in 10 per cent, 

 it sent a branch to the second interspace ; when absent, it was repre- 

 sented in the lateral thoracic .5 per cent, and in the acromio 

 thoracic 2.5 per cent. 



A. Thoracoacromialis 



This was the second branch in 47 per cent., was quite constant 

 in its point of origin, averaging 42 mm. from the beginning of the 

 artery. It sent a separate branch to the pectoralis minor in 8 per 

 cent. It had a common origin with some other artery in 24 per 

 cent. 



A. Thoracalis Lateralis 



It arose from the thoracoacromial in 12 per cent, and from the 

 subscapular in 8 per cent. In 24 per cent, it was double. The 

 distribution to the intercostal spaces was irregular, in 15 per cent, 

 the second space received no supply, while in 17 per cent, a sep- 

 arate branch from the axillary supplied this space. 



A. Suhscapiilaris 



This is the most constant branch of the group. It may come ofif 

 with the thoracoacromial, 6 per cent. Generally the circumflex 

 scapular and thoracodorsal are given ofif in the order named, but 

 in 12 per cent, the latter appears first; in 4 per cent, the circumflex 

 scapular is a separate branch from the axillary. The posterior 

 humeral circumflex is a branch of the subscapular in 10 per cent, 

 and the profunda brachii in 2 per cent. 



A. Circimifiexa Humeri Anterior 



It is usually small, it is double in 8 per cent., and is the last 

 branch of the axillary in 35 per cent. 



A. Circumfle.va Humeri Posterior 



This arises by a common trunk with the anterior in 20 per cent., 

 Quain 6 per cent., Pellegrini 22 per cent., Hitzrot 16 per cent. It 

 is associated with the subscapular in 10 per cent. 



