E AGARICINI, GILL-BEARING MUSHROOMS.

Fig. 1. Cap or pileus umbonate, _a_; stem or stipe fistulose, tubular,
_b_; gills or lamellae adnate, and slightly emarginate.

Fig. 2. Gills remote, _i. e._, distant from the stem. (See _a_.)

Fig. 3. Gills adnexed, partly attached to the stem at their inner
extremity, _a_.

Fig. 4. Gills emarginate, with a tooth, as at _a_; stem stuffed.

Fig. 5. Cap obtuse, _e_; gills free, _i. e._, reaching the stem but not
attached thereto (see _a_); _b_ stem stuffed.

Fig. 6. Cap umbilicate, slightly depressed in the centre, _b_; gills
decurrent, _i. e._, running down the stem. (See _a_.)

Fig. 7. Basidium, cell _a_, borne on the hymenium, or spore-bearing
surface of the gills; _b_, stigmata; _c_, spores.

Fig. 8. Gills adnate, _i. e._, firmly attached to the stem at their
inner extremity, as at _a_.

Fig. 9. Cap, with border involute, _i. e._, rolled inward. (See _a_.)

Fig. 10. Lamellae or gills dentated or toothed. (See _a_.)

Fig. 11. Cap with border revolute, _i. e._, rolled backward. (See _a_.)

AGARICINI. Fries.

LEUCOSPORI (SPORES WHITE OR YELLOWISH).

_Genus Lactarius_ Fries. The plants of this genus have neither veil nor
volva. They somewhat resemble the _Russulae_, but can be readily
distinguished from them by the greater fleshiness of the stem and by the
milky juice which exudes from the flesh. The latter is a characteristic
feature of the _Lactars_, giving to the group its name.

The species were originally arranged by Fries into groups according to
the color and quality of the milk, and of the naked or pruinose
character of the gills. Prof. Peck, however, considering the latter
character not sufficiently constant or obvious to be satisfactory, in
his early reports makes the color of the milk alone the basis of the
primary grouping of the American species.

Saccardo, in his Sylloge, follows Fries in his classification of the
species of the genus Lactarius.

In some species the milk is at first bright colored and continues
unchanged; in others it is always white or whitish, and in others again
it is at first white, changing to different hues on exposure to the air,
becoming pinkish, pale violet, or yellow. In one species (C. indigo)
both plant and milk are of indigo blue. The taste of the milk varies, as
does that of the flesh, according to species. Sometimes it is mild or
very slightly acrid, and again it resembles Cayenne pepper in its hot,
biting ac