The valuable herbarium, for which Muhlenberg collected and sorted for a full third of a century, was bought by a number of his friends for a little more than five hundred dollars, and was presented to the American Philosophical Society in February, 1818. It was then in good condition, but has, unfortunately, not been well taken care of, and has become so decayed as to have little if any more than historical value.
In considering the question of the value to science of these labors of a whole lifetime, we should think first of the greater clearness which resulted from them to the descriptive botany of North America. Although Muhlenberg printed but little, and although he often lost the claim to priority through being anticipated in publication by less reserved botanists, yet we find in Gray's Manual of the Botany of the Northern United States about one hundred species and varieties which were first established as such by him, and besides them a nearly equal number which were either assigned afterward to other genera, or with which, on the principle of priority in publication, the names given by other botanists were retained. This is really an admirable result, considering the zeal of collectors and hunters before and during Muhlenberg's time, and the limited extent of the field which he was able personally to examine. His services have also been well recognized by botanists. A goldenrod was given by Torrey and Gray the name Solidago Muhlenbergii; Grisebach named a centaury Erythræa Muhlenbergii; a small willow was called by Barratt Salix Muhlenbergii; and Gray gave the name Muhlenbergii to a species of reed or sedge. Two mosses of the genera Phascum and Funaria were named after Muhlenberg by Schwartz; two lichens of the genera Umbilicaria and Gyrophora by Acharius; and a fungus of the genus Dothidea by Elliott.
About half of the plant names given by Muhlenberg which are now recognized belong to the reeds and the grasses, Cyperaceæ, and Gramineæ, in the study of which he was supported by Schreber. One of the first new genera of grasses observed by him, to which belong seven species in the Northern floral region of the United States, and a still larger number of other species in the other States and Territories, was given the name Muhlenbergia by Schreber. At least five species of this genus, which have not become domiciled east of the Mississippi, are known in Colorado.
This review of Muhlenberg's botanical work would not be complete without special mention of his scientific correspondence, his personal intercourse with naturalists, and the honors he received. Among his foreign correspondents were Dillenius, Hedwig, Hoffmann, Persoon, Pursh, Smith, Schöpf, Schreber, Sturm, Willdenow, William Alton, of Kew; Batsch, the mycologist; Palisot de Beauvoir in Paris, and Dr. Thibaud in Montpellier; Christian