The vein which is part of the neuro-vascular complex of the bat's wing is a pulsatory one. We studied its histology. The fibreous conjonctive and muscular structure of the vein is particular by the presence of the adventice and a compact muscular mantle in the media. The very dense conjonctive tissue is common to the vein, the artery and the nerves showing thus the organisation of a true neuro-vascular complex.