COMMENTARY. Dioscorides, as Dr. Ainslie remarks (Mat. Ind. i, 30), has sufficiently well described this article; and yet he adds afterwards, it is a lamentable fact that the actual tree from which bdellium is got has not hitherto been clearly ascertained by botanists. He rejects the conjecture of Sprengel, although supported by the high authority of Kæmpfer and Rumphius that it is procured from the _Borassus flabelliformis_, and also that of Matthiolus, who maintained that it is procured from the _dwarf palm_, or _Chamœrops humilis_. Upon the whole, the opinion of Virey, founded on the authority of Forskael, that it is got from some species of _Amyris_, seems to be the most probable. Dr. Pereira gives the following account of this article: “The term _Bdellium_ is applied to two gummy resinous substances. One of these is Indian bdellium, or false myrrh, the bdellium of Scripture, which is obtained from _Amyris (Balsamodendron?) Commiphora_. See further Royle (Hindoos Med. p. 90.) The other kind is called _African Bdellium_, and is obtained from the _Heudolotia Africana_.” (Mat. Med. 1634.) On the _Bdellium_, see further what we have said in the Appendix to Dunbar’s Greek Lexicon. The ancients would appear to have been well acquainted with both these kinds of bdellium; at all events they were acquainted with the Indian, for Dioscorides has described it. He represents the bdellium to be calefacient, emollient, and dissolvent, and recommends it for dissolving hard tumours, for promoting menstruation in pessaries, and fumigations, and as an emetic, diuretic, and expectorant (i, 80.) The Arabians were evidently still more familiar with the bdellium than their Grecian masters; but have supplied little or no additional information respecting it. See in particular Serapion (De Simpl. 117), and Avicenna (ii, 2, 112.) Celsus recommends it frequently as an ingredient in external applications. As far as we have been able to discover, it does not occur in the works of Hippocrates. Βεττονικὴ, Bettonica, _Bettony_, is a herb having slender branches like those of the pennyroyal, but still more slender, and is possessed of scarcely any quality to the taste. It grows mostly in rocky situations, and is used for the composition of nephritic medicines. There is among the Romans another herb called bettonica, to which Dioscorides gives the name of cestrum; but others name it psychotrophon, because it delights in cold situations, having no resemblance to the aforementioned, except its medicinal powers. In addition to its action as a diuretic, it is useful for many other purposes; for its root in particular, when drunk with hydromel, occasions vomiting, and the leaves open the bowels. * * * * *