They may be simple or branched.
The small greenish flowers are borne on branched panicles; and the male ones are characterized by having a disgusting odour.
The spikelets are borne on a compound or branched spike, erect at first but afterwards bent downwards.
The peripheral paren chyma gives rise to protonephridia, that is to coiled tubes commencing in pyriform cells containing a flame-like bundle of cilia and provided with branched outgrowths, and communicating with the exterior by long convoluted canals which open at the surface of the body.
The branched intestine (G) is drawn on one side of the animal only; it opens to the exterior by means of a pharynx (not shown).