It is a native of Italy, Greece, the Greek Islands and Asia Minor, growing in waste and shady places; it is now also found throughout the greater part of the Mediterranean regions and in the Canary Islands, but whether in all instances truly indigenous is questionable. It is cultivated to some extent in Puglia, very little now near Montpellier.
History—Stavesacre was well known to the ancients. It is the ἀγροτἔρη σταϕὶς of Nicander,[23] the σταϕὶς ἀγρία of Dioscorides,[24] and Alexander Trallianus,[25] the Staphisagria or Herba pedicularia of Scribonius Largus,[26] the Astaphis agria or Staphis of Pliny.[27] The last named author mentions the use of the powdered seeds for destroying vermin on the head and other parts of the body.
The drug continued in use during the middle ages. Pietro Crescenzio,[28] who lived in the 13th century, mentions the collection of the seeds in Italy; and Simon Januensis,[29] physician to Pope Nicolas IV. (a.d. 1288-1292), describes them—“propter excellentem operationem in caputpurgio.”
Description—The fruit consists of three downy follicles, in each of which about 12 seeds are closely packed in two rows. The seeds (which alone are found in commerce) are about 3 lines in length and rather less in width; they have the form of a very irregular 4-sided pyramid, of which one side, much broader than the others, is distinctly vaulted. They are sharp-angled, a little flattened, and very rough, the testa being both wrinkled and deeply pitted. The latter is blackish-brown, dull and earthy-looking, rather brittle, yet not hard. It encloses a soft, whitish, oily albumen with a minute embryo at its sharper end.
The seeds have a bitter taste and occasion a tingling sensation when chewed. Ten of them weigh about 6 grains.
Microscopic Structure—The epidermis of the seed consists of one layer of large cells, either nearly cubical or longitudinally extended: hence the wrinkles of the surface. The brown walls of these cells are moderately thickened by secondary deposits, which may be made very obvious by macerating thin sections in a solution of chromic acid, 1 p. in 100 p. of water. By this treatment numerous crystals after a short time make their appearance,—without doubt the chromate of one of the alkaloids of staphisagria.
The outer layer of the testa is made up of thin-walled narrow cells, which become larger near the edges of the seed and in the superficial wrinkles. They contain a small number of minute starch granules and are not altered on addition of a salt of iron. The interior layer exhibits a single row of small, densely packed cells. The albumen is composed of the usual tissue loaded with granules of albuminoid matter and drops of fatty oil.
Chemical Composition—Brandes (1819) and Lassaigne and Feneulle (1819) have shown this drug to contain a basic principle. Erdmann in 1864 assigned it the formula C₂₄H₃₅NO₂; he obtained it to the extent of 1 per mille in crystals, soluble in ether, alcohol, chloroform, or benzol. The alkaloid has an extremely burning and acrid taste, and is highly poisonous.
Couerbe[30] in 1833 pointed out the presence in stavesacre of a second alkaloid separable from delphinine by ether in which it is insoluble.
The treatment of the shell of the seed with chromic acid, detailed above, shows that this part of the drug is the principal seat of the alkaloids; and the albumen indeed furnishes no crystals of any chromate. In confirmation of this view we exhausted about 400 grammes of the entire seeds with warm spirit of wine acidulated with a little acetic acid. The liquid was allowed to evaporate and the residue mixed with warm water. The solution thus obtained, separated from the resin, yielded on addition of chromic acid an abundant precipitate of chromate. The same solution likewise furnished copious precipitates when bichloride of platinum,[31] iodohydrargyrate of potassium, or bichromate of potassium were added. By repeating the above treatment on a larger scale we obtained crystals of delphinine of considerable size, and also a second alkaloid not soluble in ether.