volvulus, serratula, aster, solidago, and all the ferns. . . . The seed vessels and seeds are very important for the genus and species, and I must therefore give careful attention to them." He also indicates here as one of his purposes, besides the native plants, to observe all the exotics, whether they need protection in winter or are completely acclimated.
In the spring of 1791 he was able to inform Dr. Cutler that he had collected more than eleven hundred different plants in a circuit of about three miles from Lancaster, and that he was devoting himself to the collection of material concerning their medicinal and economical applications. In a later letter, November 8, 1791, he wrote: "I am collecting, as far as possible, all I can learn concerning the medicinal and economical uses of our plants and am writing it down. If the medicinal application seems to be sufficiently confirmed from different sides, and agrees with the character of the plant, I either try it on myself or commend it to my friends. I raise most of the grasses in my garden, and experiment how often they can be cut, and whether they are readily eaten by horses or cattle." These grasses numbered at the beginning of 1798 one hundred and fifty-six species, including many introduced ones, and among them were a large number of new species and at least one new genus. This collecting and testing of grasses is mentioned in other letters. An exchange seems to have been arranged with Prof. Schreber, of American plants for foreign grasses; and, besides mosses, grasses of New England were obtained from Dr. Cutler, especially such as grew near the sea.
Some of these notes on the medicinal properties of plants, Muhlenberg says, were furnished to Dr. Schöpf for use in his contemplated work on American Materia Medica. Although the author of that work, which was published in 1787, acknowledged indebtedness for information to several other American botanists, he does not give Muhlenberg's name—a most ungrateful omission. A similar case occurred in connection with an American book. When Muhlenberg first saw a copy of Bigelow's Medical Botany, he could not help remarking to his son, after looking through it, "This gentleman has appropriated to himself all my explanations, without making any acknowledgment." But he never called public attention to this, and there were other such trespasses which were also let pass unnoticed.
In July, 1785, Muhlenberg communicated to the American Philosophical Society an outline of a Flora Lancastriensis (flora of Lancaster) containing the results of his own observations on the plants and their habits. At the same time he presented a manuscript Calendar of Flowers. In February, 1791, he communicated the Index Flora Lancastriensis (Index to the Flora of Lancaster). This was published in the third volume of the first