Scanning electron microscopy of the trunk region of hemipenis of<i>Crotalus durissus terrificus</i>.

<p>A: Wide view of the trunk showing two cavernous bodies, one internal (CCI) and another external (CCE), near the <i>sulcus spermaticus</i> (arrowhead); the <i>musculus retractor penis magnus</i> (MRM.), spines rounding the trunk (**) and is observed that the number of <i>trabecula</i> is greater in CCE than in CCE. B: Detail of external surface of hemipenis in an area without spines, the epithelial cells (EC) covering the <i>tunica albuginea</i> (TA) of external face of hemipenis are observed. C: Detail of layers of connective tissue under epithelial cells presented in B. The connective tissue presented is non-cornified and is composed of two-to-five layers. D and E: Detail of insertion point of spine (*) in CCE in the trunk region, arrows point to smooth muscle bundles that anchor the spine in hemipenis.