This section is from the book "An Experimental History Of The Materia Medica", by William Lewis.
Abrotanum Femina foliis teretibus C. B. Santolina Chamaecyparissus Linn. Lavender-cotton: a bushy shrubby plant, all over hoary; with oblong slender leaves, composed poled each of four rows of little knobs set along a middle rib; and naked discous yellow flowers standing solitary on the tops of the stalks. It is a native of the southern parts of Europe; flowers, in our gardens, from June to near the end of summer; and holds its leaves all the winter.
This plant is supposed to agree in virtue with the foregoing abrotanum, and to be the most effectual of the two in hysteric cafes, and as an anthelmintic. It has been customary among the common people to use, in this last intention, a decoction of the leaves, made in milk; which receives from them a thick consistence, and a strong, though not very dis-agreeable taste.
On careful examination, the two abrotana appeared to differ very considerably in quality. The femina is in smell weaker and less agreeable than the mas; in taste, nauseous and acrid, but void of the penetrating bitterness which prevails in the other. Infusions, tinctures, and extracts, prepared from the femina, are more unpleasant than those of the mas, though not bitter. The essential oils of the two plants, and of conse-quence their distilled waters and spirits, approach nearer in flavour to one another, though not entirely alike.
These differences, doubtless, affect their virtues as internal medicines. Nevertheless, for fomentations, which is the principal use that either of them is applied to in the present practice, they may be looked upon as very nearly alike: hence the college of physicians of London, under the name of abrotanum, allow either the mas or femina to be taken indifferently.