This is a description sheet (with illustration) for the standard rapid cycling ideotype (RCI) or ideal form for the purple stem phenotype. Traits include high expression of purple anthocyanin, Pan(8), throughout plant; particularly noticeable on the hypocotyl, stem, hydathodes and sepals. Anthocyanin expression is strongly enhanced by environmental factors, e.g. high light and nutrient stress. Intermediate and variable expression of hair on leaves and stems, Hir(3-6). Purple anthocyanin and hairiness exhibit quantitative inheritance.