This name is a synonym of Trillium grandiflorum (Michx.) Salisb..
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 292887) with original publication details: Cat. Fl. Pl. S. Pen. Michigan 40 1874.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:258333-2.
This name was in version 1 of The Plant List, record kew-292887.