VOL. XXIir.] PHILOSOPHICAL TRANSACTIONS. 68Q 



an adult human body, filled with wax, to show the variety in nature, and sup- 

 ply the defects of the former figure, l is the aorta cut off^ at the basis of the 

 heart ; a the three semilunar valves, as they appear when the heart is in dias- 

 tole, and hinder the blood coming back from the arteries into the left ventricle 

 of the heart ; b a portion of the trunk of the arteria pulmonalis ; b b its divi- 

 sion before it passes to the right and left lobes of the lungs ; c the descending 

 trunk of the arteria magna ; d d the internal mammary arteries. 2 The trunk 

 ef the coronary cut off; 3 the ligamentum arteriosum, which in the foetus is 

 the canalis arteriosus, and conveys blood from the pulmonic artery to the great 

 artery ; 4 the trunk of the subclavian artery ; 5 5 the carotids ; 6 6 the vertebrals ; 

 7 7 the arteries which pass to the lower parts of the face, tongue, adjacent 

 muscles and glands ; 8 8 the trunks of the temporal arteries arising from the 

 carotids, giving branches to the parotid glands (Q Q) and the temples (10 lO), 

 &c. ; 1 1 11 the occipital arteries ; 12 the arteries of the fauces, gargareon, &c. ; 

 13 13 the contortions of the carotid arteries, as they pass the basis of the skull; 

 these trunks of the carotid arteries in dogs, like those I guess of most qua- 

 drupeds, are very much contorted before they reach the basis of the skull ; on 

 filling these vessels of that animal with wax, I found those branches of them 

 which pass to the brain, first clipping the hinder parts of the lower jaw, imme- 

 diately under its condyloid processes, where those arteries are received in two 

 sinuses of that bone, which sinuses may also be seen in the jaw-bones of other 

 quadrupeds, but not in human bodies ; 14 14 those parts of their trunks that 

 pass by each side of the sella turcica, whence divers small branches arise, and 

 help to compose the rete mirabile, which is more conspicuous in quadrupeds than 

 in human bodies : 15 15 the contortions of the vertebral arteries, where we find 

 their trunks considerably dilated ; l6 the vertebral arteries, as they ascend on 

 the medulla oblongata, towards the annular protuberance or pons Varolii ; 17 1 7 

 the communicant branches of the vertebral and carotid arteries; 18 18 the 

 arteries of the brain displayed. 



Fig. 3 represents one of the trunks of the arteries of the tibia, dissected 

 from the leg after amputation ; the patient was in his 67th year when this artery 

 was taken from him, and near 20 years before he lost the use of both his legs, 

 and in that time he had been so persecuted with convulsions in them, that nei- 

 ther leg was free a quarter of an hour together, whether sleeping or waking. 

 At length one of his little toes mortified, which was taken off; not long after 

 more toes of the same foot followed the like fate ; the convulsions in that leg 

 becoming stronger and quicker, that part of the foot next the toes became 

 tumid and inflamed, the tumor extending itself above the maleoli : a sinuous 

 ulcer passed by the side of one of the metatarsal bones ; the extremity of which 



VOL. IV. 4 T 



