Caenorhabditis elegans is a free-living, transparent nematode, usually measuring around 1 mm long, that lives in temperate soil situations. The name is a mix of Greek and Latin.
C. elegans has two sorts of sex: hermaphrodite and male. A hermaphrodite makes sperm when its in a larval stage and makes ova in a grown-up stage. A male can only make sperm. Males are somewhat smaller than hermaphrodites.