This name is a synonym of Magnolia macrophylla var. dealbata (Zucc.) D.L.Johnson.
The record derives from WCSP
(data supplied on 2012-03-23)
which reports it as a synonym (record 117534) with original publication details: Abh. Math.-Phys. Cl. Königl. Bayer. Akad. Wiss. 2: 373 1837.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:280259-2.
This name was in version 1 of The Plant List, record kew-117534, and has not been changed.