 In addition to the difference in length, there are also differences in the hydatid cysts of the different species.For instance, in "E. multilocularis", the cysts have an ultra thin limiting membrane and the germinal epithelium may bud externally.Furthermore, "E. granulosus" cysts are unilocular and full of fluid while "E. multilocularis" cysts contain little fluid and are multilocular.