vegetable tissue, but nourishing an insect. We know now, of course, that the four-winged insects were merely parasites of the Kermes, which lived as minute maggots within its body, destroying it and finally issuing as adult flies.
With the discovery of Mexico, things took on a new turn. Francisco Hernandez and others reported that on the tuna, or prickly pear, of that country there grew a new sort of coccus, which was much to be preferred to the one found upon the oak, or to the scarlet grain found upon the roots of plants in Poland.
This new coccus, which came to be known as the cochinilla, or cochineal, was largely imported into Europe; and eventually the cacti were brought over, and grown in Algeria, Madeira, etc., so that the dye-material could be produced nearer the market. With the impetus thus given to the study of coccus—or, as we should now say, the Coccidæ—the question as to the true nature of the material pressed anew for settlement. According to the "Encyclopædia Britannica," the idea that the cochineal was the seed or fruit of a plant was prevalent as late as 1725, but Martin Lister, in 1672, indicated its relation to the insects. In 1703, it is stated, Leeuwenhoek discovered its true nature by the aid of the microscope, "but not unnaturally supposed it to be allied to the ladybird."
This statement of the case, however, is not quite exact. We have before us a little pamphlet published as early as March, 1701, the precise date, according to a penciled figure, being the fourteenth of that month. This work is a thesis for the degree of doctor of philosophy, presented to the University of Leipzig by Frederic Friedel, and is entitled Dissertatio Physica de Cochinilla. In it, the whole question of the nature of the cochineal is fully discussed, with copious references to previous authors and many original observations.
The work consists of six chapters; the first on the name of the cochineal; the second on its habitat and the plants infested, with some interesting information on the different kinds of cacti; the third on various opinions concerning the nature of the cochineal; the fourth giving the details of the author's views as to its nature; the fifth on its culture and the methods of collecting it; and the last on its different varieties and its uses. The whole treatise is, of course, in Latin, but we give a free translation of the parts with which we are particularly concerned, abbreviating here and there.
After giving a general summary of the hitherto recorded observations and opinions. Dr. Friedel proceeds:
He then proceeds to set forth the names for the ladybird in dif-
