318 A ('(iiiiposito Study of the Sul)clavi;in Ai'lcrv in ]\lan 



V. Tlir liraiulu's of the siil)clavian artery may Ijc inore numerous in 



adults than in infants. The l)ranehes rise from all parts of the artery 



in adults, whereas in infants the branches frequently rise in a bunch 

 from Part I. 



TABLE 1.1 



The Orioin of the Arteria IMammaria Interna (Internal Mammary Artery). 



Origin. Quain. Bean. 



From I'art I 93.3 .806 



From Part II ^. 003 .000 



From Part III *. 020 .000 



From the truncns thyreo-cervicaHs 050 .097 



From a common trunk with the A. trans, scap. and the A. trans, colli. .015 .007 



From a common trunk with the A. transversa scapuliB 012 .090 



TABLE 2. 



Showing the Arterie.s that Compo.se the Truncu.s Thyreo-cervicalis (Thyroid 

 Axis) in the Different Types. 



Trunous thwen-oprvicaliscnmnnspr! of Type I Type II Type III Type IV Xot 

 iiuncus tnjieo cerMcaiiscomposeaot pig-. 2. Fig-. 3. Fijf. 4 Fig. 5. Classifleil. 



A. thyroidea inferior 1 1 1 1 



A. transversa colli 1 ) 



A. transversa scapulae 1 1 j 



T. t. c. gives off A. mammaria interna. .0 1 



Frequency of each type — Thomson 417 .413 .060 .064 ..044 



Frequency of each type — Bean 273 .257 .273 .120 .077 



TABLE 3. 



The Origin and Anomalies of the A. Thyroidea Inferior (Inferior Thyroid 



Artery). 



Orig-in. Thomson. Quain. Bean. 



As shown in Type I 432 . . . .296 



As shown in Type II 430 .900 .277 



As shown in Type IV .036 • ... .129 



From Part I (alone), as a single branch 095 .101 .287 



From the A. carotis communis 001 .003 .000 



From the A. thyroidea ima 001 .011 .009 



With the A. transversa colli 038 .005 .065 



With the A. mammaria interna , ... .046 



With the A. vertebralis 005 .001 .027 



With the A. occipitalis .018 .009 



With the A. cervicalis superflcialis 053 .025 .074 



With the A. cervicalis profunda ... .027 



Anomalies. 



Absent .022 .018 



Very large — larger than the A. suhclavia .011 .027 



Very small — not supplying the gland .014 .065 



One branch to the gland ... .046 



Two branches to the gland ... .954 



Forming both the A. occipitalis and the A. vertebralis ... .009 



1 The figures in the tables are all given in percentages or may be considered as the 

 number of times per thousand by removing the decimal i)oiut. 



