The distinctive offset small primary tubercle on interambulacral plates and their arrangement into transverse and vertical rows helps distinguish this genus. It is most unfortunate that it is the type of the family, since so much of its structure remains unknown.
Jackson, R. T. 1912. Phylogeny of the Echini, with a revision of Paleozoic species Memoirs of the Boston Society of Natural History 7, 491 pp. 76 pls.
Jackson, R. T. 1929. Palaeozoic Echini of Belgium. Memoires du Musee Royal d\'Histoire Naturelle de Belgique 38, 1-96.
Müller, J. 1856 Monatsbereichet der Akademie Wissenschaften zu Berlin fur Juni, 1856, p. 360.