308 A Composite Study of the Subclavian Artery in Man 



types. Tlie inferior thyroid artery rises from Part I, the transverse 

 cervical artery rises from Part II, and the suprascapular artery rises 

 from Part III, or from the axillary artery (9 times). This type may 

 be considered a subtype of the first, Type I, showing the extreme separa- 

 tion of the origin of the branches and no bunching. There are in this 

 type 11 male negro subjects, 4 female negro subjects, 7 male white sub- 

 jects, and 3 subjects in which the sex and race are not determined. 



Type IV (Fig. 5) is found in 12% of the cases classified, 14 times in 

 all, present in equal number on each side of the body. The inferior thy- 



AT..C. 

 T.C.C. ~^-^„ 



ATS 



RDTC. 



Fig. 5. Type IV, occurring in 12% of the specimens. 

 Fig. 1. 



For index to lettering see 



roid artery rises with a common trunk from Part I. From the common 

 trunk rise the suprascapular and transverse cervical arteries. This type 

 may be considered as a subtype of the second. Type II, in which the 

 branches are often bunched. There are in this type 4 male negro sub- 

 jects, 3 female negro subjects, 3 male white subjects, and 4 subjects in 

 which the sex and race are not determined. 



Type V (Fig. 6) occurs in 10% of the cases classified. The inferior 

 thyroid and superficial cervical arteries rise by a common trunk from 



