Schematic drawing of the anatomy of a male nematode
<ol><li>mouth opening</li>
<li>intestine</li>
<li>cloacal opening</li>
<li>organ of excretion</li>
<li>testis</li>
<li>circumpharyngeal ring of nervous system</li>
<li>dorsal trunk of nervous system</li>
<li>ventral trunk of nervous system</li>
<li>excretion pore</li></ol>
<a href="//commons.wikimedia.org/wiki/User:Uwe_Gille" title="User:Uwe Gille">Uwe Gille</a>
CC BY 2.5
<span class="int-own-work" lang="en">Own work</span>