The effects of Geomyces destructans infection on bat wings. (a) Back-lit photograph of wings of a euthanized WNS-positive little brown bat (Myotis lucifugus) with subtle circular and irregular areas of pallor (arrows) in wing membrane. (b) Back-lit photograph of the wing of a euthanized little brown with significant visible pathology associated with WNS. Area of wing membrane with relatively normal tone and elasticity (black arrow), compared to an area that has lost tone, elasticity and surface sheen, with irregular pigmentation and areas of contraction (white arrow). (c) Periodic acid Schiff-stained, 4-μm histologic section of wing membrane prepared as previously described  from a M. lucifugus showing extensive fungal infection by G. destructans. Fungal hyphae replace muscle bundles (arrows); invasion can become transdermal with associated edema (arrowhead).