Darien Center Submember of the lower part of the Wanakah Member of the Ludlowville Formation (of Brett and others, 1986, and Miller, 1991) is a well-defined 3- to 5-m interval bounded by the Mt. Vernon Bed at its base and the Bidwell Bed at its top. The Bidwell is described as a very prominent carbonate bed above the Murder Creek Bed. Name was introduced by Kloc (1983, SUNY MS thesis). It is highly condensed and contains thin graded styliolinid layers with trilobites and brachiopods. Bed is characterized by the nuculid bivalve PALEONEILO, semi-infaunal bivalves MODIOMORPHA and MODIELLA, and the archeogastropod RETISPIRA. Burrowing is extensive. Age of the Wanakah is Middle Devonian.
["Submember" not recognized as a formal stratigraphic rank term (CSN, 1933; ACSN, 1961, 1970; NACSN, 1983, 2005). Considered informal until formally published. The rank or lithologic term should not be capitalized.]

Source: GNU records (USGS DDS-6; Reston GNULEX).