Jan. 22, 1908, the right common carotid artery of a young, adult, female dog was divided, and a segment of vena cava, preserved for sixty days in formaldehyd solution, was interposed and sutured to the ends of the artery. The implanted tissue was treated with ammonia and absolute alcohol, and was impregnated with petrolatum, just prior to the operation. Feb. 12, 1908, the artery at the site of the operation was exposed, and a direct examination revealed an active circulation through the segment.1
The animal was demonstrated before the St. Louis Medical Society, Feb. 29, 1908, at which time, as far as could be determined by palpation, pulsation in the common carotid arteries was the same on the two sides.
Clinical examination, from time to time, demonstrated like pulsations in the two common carotid arteries. On the right side, at the site of operation, a dense nodular structure could