3. What's in a name?

In 1813 Englishman Adrian H. Haworth first described Epiphyllum phyllanthus and thus established the name Epiphyllum as a valid name for a Genus. However, in 1820, Link, in Germany, described the same plant as Phyllocactus phyllanthus, unaware that Haworth had already described the plant. Since Epiphyllum phyllanthus was the first name published, Epiphyllum became the valid name for this genus and phyllocactus became a synonym for epiphyllum. In fact, phyllocactus became established as a word to describe not only the epiphyllum species, but all epiphytic cacti including the hybrids produced by various epiphytic cacti plants.

There is some belief that American nurserymen in the early 1900's did not like the name "phyllocactus", but preferred "epiphyllum" and either didn't know or didn't care that in Germany "epiphyllum" did not describe all epiphytic cacti and their hybrids. Perhaps they just "assumed" that "epiphyllum" and "phyllocactus" were completely synonymous. When the Epiphyllum Society of America was established in 1940 in Los Angeles, the founding members apparently complied with this thinking. At least, this is theory proposed by some today based on articles from cacti journals and newsletters published at that time.