536 ^ USUAL CASES OF MALFORMATION. 



of the blood which comes from this organ, and especially for carrying the 

 requisite proportion of it to the substance of the heart. 



Life has existed for some time with a structure very different indeed from that 

 which is natural. In the series of elegant engravings relating to morbid 

 anatomy, published by Dr. Baillie, is the representation of a heart, in which 

 the venae cavae opened into the right auricle, and the pulmonary veins into 

 the left auricle, in the usual manner ; but the aorta arose entirely from the 

 right ventricle, and the pulmonary artery as completely from the left. The 

 canalis arteriosus, however, passed from the pulmonary artery to the aorta, 

 and the foramen ovale existed. In this case, it is evident, that the pulmonary 

 artery must have carried back to the lungs the arterial blood which came 

 from them by the pulmonary veins, with a small quantity of venous blood 

 that passed into the left auricle through the foramen ovale; and that the aorta 

 must have returned to the body the venous blood, which just before had been 

 brought from it by the venae cavae, with a small addition of arterial blood 

 that passed through the ductus arteriosus. Yet with this structure the child 

 lived two months after its birth. 



A case, which had a strong resemblance to the foregoing, occurred in Philadel- 

 phia, and was examined by the author of this work. The venae cavae termi- 

 nated regularly in the right auricle, and the pulmonary veins in the same 

 regular manner in the left ; but the pulmonary artery arose from the left 

 ventricle, and the aorta from the right. There was no communication between 

 these vessels by a canalis arteriosus ; but a large opening existed in the septum 

 between the auricles. 



It is very evident, that, in this case also the pulmonary artery must have 

 returned to the lungs the arterial blood as it came from them, and the aorta 

 must have carried back to the general system the venous blood brought to 

 the heart by the cavae j excepting only those portions of the arterial and 

 venous blood which must have flowed reciprocally from one auricle into the 

 other, and thus changed their respective situations. 



The subject was about two years and a half old. The heart was nearly double 

 the natural size, and the foramen, or opening in the septum between the 

 auricles, was eight or nine lines in diameter. The pulmonary artery was 

 larger in proportion than the aorta or the heart. 



With this organization, the child lived to the age above specified. His 

 countenance was generally rather livid ; and this color was always much 

 increased by the least irregularity of respiration. His nails were always 

 livid. He sometimes appeared placid, but more frequently in distress. He 

 never walked, and seldom, if ever, stood on his feet. When sitting on the 

 floor, he would sometimes push himself about the room; but this muscular 

 exertion always greatly affected his respiration. He attained the size 

 common to children of his age, and had generally a great appetite. For 

 some weeks before death his legs and feet were swelled. 



It is probable that the protraction of life depended upon the mixture of the 

 blood in the two auricles ; and that they really were to be considered as one 

 cavity, in this case. 



There seems reason to believe, that in adults of the common structure, there is 

 no passage of blood from one auricle to the other, when the foramen ovale 



