The resulting code was formulated as a supplement to the existing International Code of Botanical Nomenclature.[127][128][lower-alpha 21] Stearn introduced two important concepts, the terms "cultivar" and "grex". Cultivar, a term first proposed by L. H. Bailey in 1923,[129] refers to a distinctive genus or species variety raised or maintained in cultivation, such as Euphorbia dulcis "Chameleon".