Fig. 1. Scanning electronmicrograph of a single glomerulus from a superficial loopless (reptilian-type) avian glomerulus (Anna's hummingbird). Vessels are filled with microfil. Vessel coming into glomerulus from left is the afferent arteriole. Vessel leaving glomerulus on the right is the efferent arteriole. Glomerular capillary exists as a single loop of capillary. Scale bar, 10 µm. Unpublished picture courtesy of Eldon J. Braun.