Moore 1957 describes this plant under the name "Musa Maurelii" which may have been interpreted by some as raising it to species status.  However, this was not Moore's intention and he states specifically that the binomial "Musa Maurelii" has no proper botanical standing under the International Code of Botanical Nomenclature.

Some nurserymen do however regard 'Maurelii' as a distinct species of Musa or Ensete and it is interesting to note that Bois himself was rather unsure as to what the plant before him actually was.  In his 1930 paper, Bois named two "red-leaved bananas".  The first plant he readily recognised as a form of Musa ensete that he named var. Montbeliardi, which, formalised by Cufodontis 1972, is now understood to be a form of Ensete ventricosum.  The second plant was so different in habit to the first that Bois doubted that it was Musa ensete but instead a form of an unknown Musa.

Although Bois was not able precisely to identify the second plant it is possible from the context of the "discovery" of the plants by Maurel and from Bois' paper to deduce i) that both plants are Ensete ventricosum (it is now known that there are no African Musa and no other species of Ensete occurs in Ethiopia) and ii) that both are cultivated varieties (cultivars) and not naturally occuring varieties growing and reproducing themselves in the "wild". 

The physical difference between 'Maurelii' and 'Montbeliardii' is indeed striking, 'Maurelii' short and squat, 'Montbeliardii' tall and elegant, (see Graf for photographs) but this simply reflects the polymorphic nature of Ensete ventricosum.  That the plants are cultivated forms and not wild forms means that the names given by Bois should properly have cultivar status and be written e.g. 'Maurelii' and not maurelii.  Finally, to accord with modern practise under the International Code of Nomenclature of Cultivated Plants, cultivar names commemorating a person should (in this case) end in "ii".

Both 'Maurelii' and 'Montbeliardii' were introduced into the U.S.A. by David Barry Jr. and released through his California Jungle Gardens in Los Angeles.  Although 'Maurelii' is still widely available in the U. S. and Europe I (drc) have been quite unable to locate a plant of 'Montbeliardii'.

'Maurelii' is sometimes offered commercially as 'Atropurpureum' or 'Rubra' or 'Rubrum' but these are invalid names.   Further, there is no discernible difference in the plants on different U.K. nurseries to warrant such a distinction.  Any differences reported are due only to cultivation conditions that can have quite profound effects on plant colour and morphology.

Images:

There are 3 images of Ensete ventricosum 'Maurelii' and links to 2 external images.