Oil of Lemon (Oleum Limonis),
obtained from the fruits of the lemon-tree, is one of the most important products, both statistically and economically, of the Citrus family. In German works there is often a confusion between “oil of citron” and “oil of lemon,” it being supposed by the authors that the “Citronen-öl” is derived from the citron (Citrus medica), and the “Limonen-öl” from the lemon (Citrus Limonum). There is, indeed, some oil made, occasionally, from the citron, but it does not figure in price-lists. The oil of the lemon, on the other hand, is very commonly called “Citronen-öl,” and the fruit itself “Citrone.” Hence, when “Citronen-öl” is quoted in a formula, it may be assumed at once that oil of lemon is intended. It is very liable to resinify, when it loses its fragrance.