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ral ; and it was evident, even from external examination, that there 

 were two spines corresponding to the two heads. These were found 

 to terminate in a double os sacrum, tipped with two ossa coccygis ; 

 there were consequently two vertebral canals, independent of each 

 other. The chest in front was nearly as usual, with the common 

 number of ribs on each side ; but there were also, in the middle of 

 the back, short bones, which must be considered as ribs connecting 

 the two spines to each other. 



The chest was divided by its mediastinum into two cavities. In 

 the right was one lung connected with the right head, and in the 

 left another belonging to the left head, without any mutual commu- 

 nication. On inspecting the vascular system, there were found to be 

 two hearts ; that on the left, and corresponding with the male head, 

 was much the larger of the two ; but they both had the usual num- 

 ber of auricles, and were inclosed in separate pericardia. 



The principal difference in the distribution of their vessels was ob- 

 servable in the veins ; as the vena cava superior was wanting on the 

 right side, and the right heart received its blood by the vena cava 

 inferioK alone ; while that on the left had its principal supply by a 

 large vena cava superior, which brought the blood from the jugulars 

 of the right head and right subclavian, as well as from those of its 

 own side. But, on the contrary, the vena cava inferior was com- 

 paratively very small. 



With respect to the arteries, the difference was not considerable, 

 as they each sent off their respective aorta and pulmonary artery, 

 and each supplied their respective head by two carotids, and their 

 corresponding arm by one axillary artery ; after which the two 

 arches united into one trunk as descending aorta. 



Little irregularity was observable in the cavity of the common ab- 

 domen, the stomach of which was connected with an oesophagus from 

 the left head ; but in a second abdominal cavity, formed by an ob- 

 lique position of the diaphragm, there was also a smaller stomach 

 belonging to the right head, with a spleen, pancreas, and omentum ; 

 but the duodenum from this stomach soon communicated with that 

 from the left side, and the remainder of the intestinal canal was con- 

 tinued onwards, with little deviation from the natural structure. 



The organs of generation were very remarkable, as they distinctly 

 partook of both sexes ; for though, in the external parts, the charac- 

 ter of the male was predominant, with two testes in the act of pass- 

 ing into the scrotum, yet, in some respects, certain deviations be- 

 longing to the female were even here apparent ; and, upon internal 

 examination, an uterus was discovered imbedded in the posterior 

 part of the bladder, from which Fallopian tubes were given off at 

 each side near its upper part. 



The author next examined carefully the distribution of the nerves, 

 and found, in general, extremely little connexion between them, ex- 

 cepting at the semilunar ganglion, which was composed of nerves 

 derived equally from both sides. 



Each brain, for instance, gave origin to an eighth pair of nerves, 



