Scanning electron microscopy of Chilomastix mesnili shows that the cysts ar
e lemon-shaped with one end broadly rounded and the other conical. The trop
hozoite has five flagella coming out of the anterior end. Four of these are
free and the fifth is attached to the body by an undulating membrane. The
undulating membrane extends along the whole length of the body of the paras
ite with the exception of the tail. The tail is an elongated structure almo
st equal in length to the main body of the parasite.