Abstract
The morphological characters, which can be used in differential diagnosis, of the eggs, larvae, adults and cysts of the 6 economically important Heterodera species in Europe (H. rostochiensis, H. schachtii, H. avenae, H. goettingiana, H. trifolii and H. carotae) are reviewed. About 80 references are cited. The dimensions of certain organs of the species, as reported by various authors, are compared in tables.