Specimens were received in June, 1898, from Dr. Post of Lansing, Mich., which were collected there in a potato patch. It was abundant during May and June. Plants which were sent in a fresh condition were badly decayed by the time they reached Ithaca, and the odor was very disagreeable. It is remarkable that the odor was that of rotting potatoes! In this connection might be mentioned Dr. Peck's observation (Bull. Torr. Bot. Club 26: p. 67, 1899) that _Agaricus maritimus_ Pk., which grows near the seashore, possessed "a taste and odor suggestive of the sea." McClatchie reports that it is common in cultivated soil, especially grain fields and along roads, and that it is "a fine edible agaric and our most abundant one in California." CLITOPILUS Fr. In the rosy-spored agarics belonging to this genus the gills are decurrent, that is, extend for some distance down on the stem. The stem is fleshy. The gills are white at first and become pink or salmon color as the plants mature, and the spores take on their characteristic color. The plants should thus not be confused with any of the species of _Agaricus_ to which the common mushroom belongs, since in those species the gills become dark brown or blackish when mature. The genus corresponds with _Clitocybe_ among the white-spored ones. =Clitopilus prunulus= Scop. =Edible.=--This species grows on the ground in the woods from mid-summer to autumn. It is not very common, but sometimes appears in considerable quantities at one place. During the autumn of 1898 quite a large number of specimens were found in a woods near Ithaca, growing on the ground around an old stump. The plants are 3--8 cm. high, the cap 5--10 cm. broad, and stem 1--2 cm. in thickness. [Illustration: PLATE 44, FIGURE 138.--Clitopilus prunulus, cap whitish or dark gray, gills flesh color (natural size). Copyright.] The =pileus= is fleshy, firm, convex and becoming nearly plane, and sometimes as the plants become old the center may be slightly depressed. It is whitish in color, or dark gray, or with a leaden tint, dry, sometimes with a distinct bloom on the surface, and the margin is often wavy. The cap is sometimes produced more on one side than on the other. The =gills= are not close, at first whitish, then salmon colored as the spores mature, and they are decurrent as is characteristic of the genus. The =spores= are elliptical or nearly so, and measure 10--12 µ long. Figure 138 is from plants collected near Ithaca, in the autumn of 1898. This species is considered to be one of the excellent mushrooms for food. When fresh it has a mealy odor and taste, as do several of the species of this genus. It is known as the prune mushroom.