The scarlet grain of Poland, _Coccus polonicus_, found on the German knot-grass or perennial knawel (_Scleranthus perennis_), was at one time collected in large quantities in the Ukraine and other provinces of Poland (here under the name of _Czerwiec_), and also in the great duchy of Lithuania. But though much esteemed and still employed by the Turks and Armenians for dyeing wool, silk, and hair, as well as for staining the nails of women’s fingers, it is now rarely used in Europe except by the Polish peasantry. A similar neglect has attended the Coccus found on the roots of the Burnet (_Poterium sanguisorba_, Linn.), which was used, particularly by the Moors, for dyeing wool and silk a rose color; and the _Coccus uvæ-ursi_, which with alum affords a crimson dye.[903] Cochineal, the _Coccus cacti_, is doubtless the most valuable product for which the dyer is indebted to insects, and with the exception perhaps of indigo, the most important of dyeing materials. It is found on a kind of fig, called in Mexico, where the insect is produced in any quantity, Nopal or Tuna, which generally has been supposed to be the _Cactus cochinilifer_, but according to Humboldt is unquestionably a distinct species, which bears fruit internally white. Cochineal was discovered by the Spaniards, on their first arrival in Mexico, about the year 1518; but who first remarked this valuable production, and made it known in Europe, Mr. Beckman says, he has been unable to discover. Some assert that the native Mexicans, before the landing of Cortes, were acquainted with cochineal, which they employed in painting their houses and dyeing their clothes; but others maintain the contrary. Be that as it may, however, the Spanish ministry, as early as the year 1523, as Herrera informs us, ordered Cortes to take measures for multiplying this valuable commodity; and soon after it must have begun to be quite an object of commerce, for Guicciardini, who died in 1589, mentions it among the articles procured then by the merchants of Antwerp from Spain. Professor Beckman, who has given the subject particular attention, thinks that with the first cochineal, a true account of the manner in which it was procured must have reached Europe, and become publicly known. Acosta in 1530, and Herrera in 1601, as well as Hernandez and others, gave so true and complete a description of it, that the Europeans could entertain no doubt respecting its origin. The information of these authors, however, continues this gentleman, was either overlooked or considered as false, and disputes arose whether cochineal was insects or worms, or the berries or seeds of certain plants. The Spanish name _grana_, confounded with _granum_, may have given rise to this contest.