Upper: capillary endothelial cell junction in the rete mirabile of the gas bladder of the toadfish Opsanus tau shows dense intracelluular plaques and the central dense line in the intercellular space, characteristics that define desmosomes. Flanking this junction are other smaller and less highly organized densities with few, or no tonofilaments (asterisks). Lower: Desmosomes are abundant in the stratum spinosum of the epidermis from the muzzle of the cow, Bos taurus, an epithelium that is constantly subjected to flexion and attrition during grazing. Lower image contributed by Gida Matoltsy. Figures 85 (upper) and 86 (lower) from Chapter 3 (Junctional Specializations) of 'The Cell, 2nd Ed.' by Don W. Fawcett M.D. A PDF copy of the accompanying chapter is available on the ASCB's BioEDUCATE website.