The Pittsburg National Stockman says:

"The word gladi-o-lus, accented on the antepenultimate (the i in the present instance) according to rule, is not easily pronounced by many until after considerable use; hence it has often had the accent erroneously placed on the penultimate, 0. There is a disagreement also in regard to the plural form, in which the right and wrong are less distinctly marked; some good botanists considering that as the word has been fully Anglicised it should take the English plural, gladioluses; while others, including most of the bulb-catalogues, retain the Latin plural, gladioli. Recently Prof. Meehan, of Philadelphia, who has been understood as favoring the English plural above, has been using, in the Gardeners' Monthly, of which he is the accomplished editor, the word gladiolas, the singular of which would be gladiola. This is a comparatively new word; and while there is no change of the accent the termination is changed, shortening the word and at the same time ridding it of the English superabundant ss which is objectionable to some.

"The divergence having thus been begun, each may be at liberty to choose between gladioluses and gladiolas. And at the same time it may be well to consider whether it would not be better to change the accent to 0; as Stormonth, a recent English dictionary of high repute, after giving the established pronunciation of the old word, gladiolus, accenting the i, adds: "popularly, gladi-o-lus." Thus, the recent words would be, gladi-o-la and gladi-o-las - if the innovation is to be allowed".

We may add to the above that it is not the first time words have been changed in their genders and pronunciations to suit English needs. If we follow ancient examples with faultless precision, we should say, Anem-o-ny, instead of An-em'-ony, ar'-butus, instead of ar-bu-tus, sed'-um, instead of se'-dum, and so forth; and if by making gladiolus feminine instead of masculine, we bring gladiolus more in accord with the shape of our tongues, we have at least some precedents as our warranty.

There seems to have been no rules for the ancient classifications of Latin gender in nouns except peculiarities of pronunciation.