m 
very unusual Formation of the human Heart. 
sence of Dr. Poignand ; when the heart, as was previously 
suspected, appeared to be situated in the epigastric region of 
the abdomen, and to be imbedded, as it were, in a cavity 
formed on the superior surface of the liver. In this state, the 
child was sent to Dr. Baillie, by whose desire I injected the 
heart, and laid its principal vessels bare, so as to bring their 
uncommon distribution and course into view : a preparation of 
them still remains in Dr. Baillie" s possession. 
A considerable part of the tendinous portion of the dia- 
phragm appeared to be wanting, as likewise the lower part of 
the pericardium, which is usually affixed to it. The thorax 
being laid open on each side of the sternum, the two pleurae 
were seen passing from that bone to the spine, and covering 
the lungs, as usual. The lungs appeared perfectly natural in 
colour, and nearly so in shape ; but were larger and fuller than 
usual, in consequence of more room being afforded for them in 
the thorax, from the peculiar situation of the heart. In the 
space corresponding to the anterior mediastinum, was the thy- 
mus gland, considerably longer than in other children, and 
extending downwards the whole length of the sternum ; be- 
hind this, was a peculiar arrangement of blood-vessels. 
The heart, instead of consisting of four cavities, as in the 
natural structure, consisted of a single auricle and ventricle, 
which were each of them large in their size. A large arterial 
trunk arose from the ventricle, and ascended into the thorax, 
between the pleurae, immediately behind the thymus gland : it 
soon divided into two large branches, one of which continued 
to ascend, forming the aorta ; the other passed backwards, and 
proved, upon examination, to be the pulmonary artery. 
The aorta, having reached the common place of its curva- 
