(Redrawn after Lumsden and Specian 1980)
Hymenolepis have a short, wide proglottid with three testes. One testis is on the same side as the genital pore,and the other two are aporal, on the opposite side. There are large external and internal seminal vesicles. The female system has a central uterus with a compact vitellarium just behind it, and a posterior uterus. There is a prominent seminal receptacle.