This name is a synonym of Mimulus lewisii f. albus (J.K. Henry) B. Boivin.
The record derives from Tropicos
(data supplied on 2012-04-18)
which reports it as a synonym (record 50102161) with original publication details: Fl. S. Brit. Columbia 268 1915.
Full publication details for this name can be found in IPNI: http://ipni.org/urn:lsid:ipni.org:names:161772-2.
This name was in version 1 of The Plant List, record tro-50102161.