There are only three species of citrus fruits: Citrus medica (citron), Citrus maxima (Chinese grapefruit) and Citrus reticulata (tangerine) Lemon, lime, rough lemon, bitter orange, blood orange, sweet orange, grapefruit, kafir lime, bergamot, finger lime – are the result of their hybridizations. There is a person in Spain who guards a garden of delights where all of them can be seen; up to 400 varieties.