Gastrotrichs include small, ventrally flattened animals about 65-500 µm long looking somewhat like rotifers but lacking the crown of cilia and the mastax and having bristly or scaly body. They are normally found gliding on the surface of plants or bottom by means of their ventral cilia. They are closely related to the rotifers in having cilia, protonephridia, and a similar muscle pattern. On the other hand, some characteristics are more similar to those of nematodes.  The digestive system of Gastrotrichs is complete and is made up of a mouth, muscular pharynx, stomach-intestine, and anus. Their food is largely algae, protozoans, and detritus. Gastrotrichs are hermaphroditic, but the male portion of the chaetonotids is so poorly developed that they are functionally parthenogenetic females. The female reproductive system consists of one or two ovaries, a uterus, an oviduct, and a gonophore, which may open anteriorly to, or in common with, the anus. Eggs are laid on some substratum such as weeds and hatch in a few days.