Following small bowel transplantation, new lymph vessel anastomoses form spontaneously. Surgical anastomoses of the lymphatic vessels are unnecessary. The formation occurs in three stages. To the second postoperative day, lymph stays within the lymphatic vessels of the transplant. Following the fourth postoperative day, lymph flows within preexistent adventitial lymphatic vessels along the transplanted mesenteric artery to the arterial anastomosis at the aorta and stops there. From the sixth postoperative day on, lymph crosses the arterial anastomosis for the first time and flows along the recipient's aorta. To the eighth postoperative day a new lymph anastomosis is formed between the adventitia of the aorta and the neighbouring major lymphatic vessels. In the experiments presented here, these are represented by the vasa lymphatica testicularia sinistra of the recipient. Thus, the new anastomosis between lymphatic vessels is complete on the eight postoperative day. These new vessels gradually dilate with time.