Surface view of an artery from the mesentery of a frog, ensheathed in a perivascular lymphatic vessel. Labels: a, The artery, with its circular muscular coat (media) indicated by broad transverse markings, with an indication of the adventitia outside. 1. Lymphatic vessel: its wall is a simple endothelial membrane.

Surface View of an Artery

Surface view of an artery from the mesentery of a frog, ensheathed in a perivascular lymphatic vessel.…