Robert Bennett Beau 313 



Two striking features are noticed. In the first place there seems 

 to be a tendency for the branches to be bunched from Part I. The inter- 

 nal mammary artery arises 4 times with the thyroid axis, and the supra- 

 scapular artery arises twice from the internal mammary artery. In the 

 second place the suprascapular artery is small in five cases, and does not 

 extend beyond the suprascapular notch in these cases, its place being 

 taken by the dorsal scapular artery. There are 2 other cases with inoscu- 

 lation around the neck of the scapular between these two arteries, the 

 suprascapular being like a continuation of the dorsal scapular artery. 

 Knowledge of the previous condition of the subject as to age, habits, and 

 family history, and dissection of subjects that had died at the ages of 1, 

 5, 10, 15, 20, and 25 years, etc., would be of value in studies similar to 

 this one. 



Foiirih. — There are 74 male negro and 16 female negro subjects, and 

 21 male white and 3 female white subjects from which records were made. 

 In 15 subjects the race and sex are not determined. In view of the 

 small number of female and white subjects, the relation of sex and race 

 will hardly admit of discussion. Many of the subjects are mulattoes, 

 or mixed bloods. The number of anomalies, variations, and queer types 

 is uncommonly large. 



May we not explain the occurrence of this large number of abnormali- 

 ties by the well-known biological law that hybrids tend toward variation ? 

 The question is an open and an interesting one. 



Fifth. — Free anastomoses by a definite arterial trunk were found in 

 connection with the suprascapular, deep cervical and superior inter- 

 costal arteries. The suprascapular artery inosculates with the dorsal 

 scapular artery posterior to the neck of the scapula, 17 times, or in 16% 

 of all cases. The trunk was from 2 to 5 mm. in diameter. The superior 

 intercostal artery anastomoses with the superior aortic intercostal artery 

 31 times, in every case where it is looked for. The anastomosis is found 

 to take place : 



At the second intercostal space IG times 



At the third intercostal space 10 times 



At the fourth intercostal space 5 times 



The trunk is very small, only a minute tube in some cases. The 

 deep cervical, " profunda cervicis," anastomoses with the " princeps cervi- 

 cis " from the occipital in 11 cases, 10% of all. The trunk is of good 

 size, frequently about 5 mm. in diameter. 



Sixt]i. — Anomalies when present are found as a rule on each side of 

 the same subject. Tlie most frequent anomaly met with in the dissec- 

 25 



