However it has no official recognition by the International Commission on Stratigraphy (ICS) and has been superseded by the more recently defined Ibexian series of western Utah.
Flower (1957 p. 17) felt that recognition of the Canadian as a separate system would greatly solve problems in Early Paleozoic stratigraphy.
Flower however (1957, 1964) separated the Canadian from the rest of the Ordovician and defined it as a four-part system, divided in ascending order into the Gasconadian, Demingian, Jeffersonian, and Cassinian which stands today.
The remaining Ordovician was also divided (Flower 1964, fig 3 p. 23) into four parts, the Whiterockian, Chazyan, Mohawkian, and Cincinnatian.
Starting at the bottom: All four stages of the Canadian, except for the uppermost Cassinian, are represented in the El Paso Group in New Mexico and West Texas.