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This and not M. × watsonii Hook.f. is the correct name for M. hypoleuca × M. sieboldii (S. Spongberg, op. cit., p. 272). It is founded on another plant exhibited at the Paris Exposition of 1889, bought by a Monsieur Wiesener of Fontenay-aux-Roses and named by Carrière in 1890. It probably represented a different clone from that from which M. × watsonii was described in the following year.