extraordinary Human Foetus* 125 
outside of each spine ; and between the inner sides of the 
spines, occupying the space formed by their divergence, was 
interposed an equal number of somewhat angular ribs, of 
about an inch in length. These were common to both spines, 
and possessed a considerable latitude of motion, but were un- 
connected with any bone similar to the sternum. These short 
ribs, by occupying the situation of the spine in the natural state 
of the body, completed the posterior part of the chest. 
The only remaining peculiarities in the osseous system, 
was a third scapula, small in size, and placed at the root of 
each neck, upon the small ribs ; and a third clavicle, inserted 
at one extremity into the glenoid cavity of this scapula, and 
attached by the other to the upper part of the sternum. 
Before I proceed to describe the conformation of the vas- 
cular system, and the distribution of the nerves of the thoracic 
and abdominal viscera, it will be necessary, first to notice the 
arrangement, connection, and number of these viscera. 
The chest was divided by the mediastinum into two cavi- 
ties, containing, amongst other organs, the lungs, and two 
hearts, placed contiguous to each other. It was ascertained 
by inflation, that the lungs on the right side were entirely 
independent of those on f he left, each being supplied with air 
by a distinct trachea, from the corresponding head. They 
were not divided into lobes in the usual way : on the right 
side there were only two lobes, on the left only one. The 
only peculiarity with respect to the diaphragm was, that 
instead of being attached to the spine and lower ribs, on the 
right side of the body, it crossed over a considerable portion 
of the right lobe of the liver ; this muscle, therefore, assisted 
in forming a cavity, which was situated upon the two spines,. 
