In the course of dissection the authors revealed several—from 2 to 8—perforating branches in the peroneal artery instead of only 1 as stated in the text-books. These branches,after perforating the interosseous membrane, supplied the extensor muscles of the leg and might form anastomosis with the anterior tibial artery.On the other hand,the anterior tibial artery was also found to send twigs to perforate the interosseous membrane, anastomosing with the peroneal artery or supplying the muscles of the back of the leg. These communications might be explained by the change in the course of the arteries of the leg during embryonic development.Any failure in the disappearance of the horizontal communications between the embryonic longitudinal vessels would result in a feature as found by the authors.