http://gotheborg.com/marks/noritake.shtml

This will tell you about the Morimura brothers which is what the M stands for !! Your plate or bowl was made after 1921 and before 1940 !! The Morimura brothers were Japanese based importers and later moved to NY !! So much was imported into the U.S. that finding the pattern would be difficult and much did not have a pattern name just a number !! I have not seen this mark before but that is not unusual !! They have documented 359 different marks and many variations of the wreath mark used by them !!