This name is a synonym of Magnolia tripetala (L.) L..
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 117587) with original publication details: Prodr. Stirp. Chap. Allerton 379 1796.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:554710-1.
This name was in version 1 of The Plant List, record kew-117587, and has not been changed.