Duthie, in his 1888 work, inadvertently published “Iseilema laxum Hack.” as a superfluous, illegitimate name for the 1856 name I. prostratum (L.)Anderss. The subsequent 1889 publication of I. laxum by Hackel, which excluded the type of I. prostratum, is, therefore, heterotypic, a later homonym, and illegitimate. A new name is here proposed for “Iseilema laxum Hackel 1889 (non Hackel 1888).”