Arterial Anomalies 59 
particularly to arrest of development; and the other, section III, 
relating to fusion or separation of branches of the aortic arch. 
Since all of the evidence goes to show that the several disturbing 
developmental factors may operate independently of each other, 
these figures have no statistical value except to show the relative 
frequency of the cases included in this study. : 
The anomalies of the thoracic duct can all be explained from 
the embryological development. The duct shows less tendency to 
irregular development than the arteries of the same region, and 
the duct irregularities are independent of arterial variations ex- 
cept in so far as developmental disturbances affecting the ar- 
teries may be so far reaching as also to affect the thoracic duct. 
St BIBLIOGRAPHY 
AxsgoTt, F. C. 1892. Specimen of right aortic arch. Journ. Anat. and 
Physiol., vol. 26, p. 13 (Proceedings). 
—— 18 92a. Anomalous arrangement of branches from the arch. Journ. 
Anat. and Physiol., vol. 26, p. 15 (Proceedings). 
ABERCROMBIE, J. 1881. Congenital imperfection of the septum ventricu- 
lorum with attending thrombosis of the right ventricle and pulmonary 
artery. Trans. Path. Soc., London, vol. 32, p. 73-74. 
—— 1883. Congenital atresia of the right ventricle, ductus arteriosus 
patent. Trans. Path. Soc., London, vol. 34, p. 78. 
ABERNETHY, J. 1793. An account of two instances of uncommon forma- 
tion in the viscera of the human body. Phil. Trans. London, vol. 83, 
p. 295. 
Apacui, B. 1914. Beitrage zur Anatomie der Japaner. Die Varietaten 
der Verzweigung des Arcus Aortae. Zeitschr. f. Morph. u. Anthropol., 
Bd. 18, S. 227-240. 
Arsy, C. 1871.. Der Bau des menschlichen Korpers. Lipsiae. 
AGLIETTE, —. ——. (Right aortic arch.) Saggi. de Padova, tom. I, p. 69. 
AHLFELD, F. 1880. Die Misbildungen des Menschen. Leipzig. 
1888. Angeborene Misbildungen und Erkrankungen aus der Klin. 
zu Marbourg. Leipzig. 
ALAMARTINE, L. 1888. Note sur un cas d’absence congenitale d’une val- 
vule sigmoide de l’aorte. Loire méd. et Etienne, tom. 7, pp. 205-209. 
Aezais, H. 1880. Deux nouveaux cas d’anomalies cardiaques. Gaz. d. 
Hop., tom. 53, p. 890. 
ALEZAIS ET GILLy. 1887. Rétrécissement congenital de l’aorte descendente. 
Marseill. méd., tom. 24, pp. 594-608. 
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