m

589-2>'2*

K89-f

Field Key

to the

Genera of the

Gill Mushrooms

by

Louis C. C, Krieger'

The Norman, Remington Co.

Baltimore

1920

MM

583.22.

K89-P

Field Key

to the

Genera of the

Gill Mushrooms

The Norman, Remington Co.

Baltimore

Under Colly hi
Marasmius.”

Under Panaec
poisonous; car

Copyright, 1920, by

Louis C. C. Krieger

23J&ZO r&cJ

THE STRUCTURAL PARTS OF
GILL-MUSHROOMS

The figures in parentheses refer to the large

numbers in the spaces of the key.

Fig. 1. (a) Warts, or remains of the volva (d), to be
found on the caps or pilei (sing, pileus)
of some Amanitae (1).

(b) Gills free from the stem, or stipe.

(c) Inner veil, also called annulus or partial
veil.

(d) Volva, also called outer or universal veil.
This tissue, which may be membranous
or crumbling (“friable”), originally en-
closes, like a bag, young plants belonging
to Amanita (1), Amanitopsis (2), etc.

Fig. 2. Cap umbilicate (b). Gills decurrent (a).
The term “arcuate” describes a similar mode
of gill- attachment (See 7, 79, 15, 33, 51, and
69).

Fig. 3. Cap umbonate (a). Gills emarginate or
sinuate (b). A decurrent “tooth” is also
shown. (See 5, 41, 14, and 32).

Fig. 4. Cap conic or campanulate (some species of
Coprinus [74], 45, 81, 10, 13, 31, 49, 67, and
87). Gills ^dnexed (a), i.e., narrowly
attached to the stem.

Fig. 5. (a) Gills somewhat emarginate, or rounded
behind, but without a decurrent “tooth.”
Cap slightly umbonate and expanded.

Fig. 6. Cap convex, approaching semi-globose. Gills
adnate, broadly or squarely so (a). The
degree of adnateness varies from an ap-
proach to adnexed to almost decurrent.
Some gills (adnexed, adnate, or decurrent)
are loosely attached to the stem, and, there-
fore, “secede’ ’ readily. Such spurious “free-
ness” must be carefully differentiated from
the true.

5-

EXAMPLE ILLUSTRATING THE USE OF THE
FIELD-KEY

We wish to learn the generic name of a certain
gill-mushroom. An examination of its structure
shows it possesses a ring on the centrally placed
stem; there is no volva at the base of the stem, nor
do we find fragments (“warts”) of this tissue on the
top of the cap; the gills are free, and the spore-print
(obtained by the method described above) is purple-
brown. The color of the spore-print places it in the
fourth spore-color group (see left side of Key), while
the presence of a ring and the absence of a volva
refer it to the third division by structures (see cap
tions above the Key). Its stem being central, and
its gills non-waxy and free, we look down the Key,
meet the horizontal row of purple-brown spored
agarics, and at the point of intersection we learn
the genus name of our plant, Agaricus. The genus
is a fairly large one, comprising well over one hundred
species for the world. Agaricus campester, the
common meadow mushroom, is a well-known
representative.

HOW TO ASCERTAIN THE COLOR OF THE
SPORES

To determine a mushroom generically it is not
only necessary to make careful notes on the struc-

ture, but the color of the spores must be ascertained
as well. To infer this color from the color of the gills
is likely to lead to error. As it is important to avoid
error in so fundamental a matter, a deposit of the
spores themselves should be obtained. Such a spore-
deposit (“spore-print”) can be secured from a fresh,
mature or maturing specimen by cutting off the stem
near the cap and placing the cap, gill-side lowermost,
on two sheets of paper, one white and the other
black, the sheets being so disposed as to receive equal
amounts of the spore-rain. The length of time re-
quired for the formation of a sufficiently dense
deposit varies somewhat, but in an hour enough
spores will have fallen to enable one to decide as to
their color. A glass bowl or a large cup should be
used as a cover, otherwise the microscopic spores
will be blown about by air currents.

INDEX TO THE NAMES OF THE GENERA IN
THE KEY

The names in italics are used by some writers in

place of those adopted here. The figures refer to
the spaces.

Acetabularia 38

Laccaria 15

Agaricus 57

Lactarius 16

Amanita 1

Lentinus 18

Amanitopsis 2

Lenzites 18

Anellaria 77

Lepiota 3, 4

Annularia 21

Leptonia 30

Anthracophyllum 90

Limacium 7

Armillaria 6

Locellina 38

Arrhenia 17

Marasmiopsis 40

Bolbitius 45

Marasmius 18

Camarophyllus 15

Metraria 19

Cantharellus 15

Montagnites 74

Chalymotta 77

Mycena 13

Chamaeota 21

Naucoria 48

Chitonia 56

Nolanea 31

Chitoniella 55

Nyctalis 52

Clarkeinda 56

Omphalia 15

Claudopus 35

Panaeolus 87

Clitocybe 15

Panus 18

Clitopilus 33

Paxillus 51

Collybia 12

Pholiota 41

Coprinus 74

Pilosace 65

Cortinarius 41

Pleurotus 8, 17

Cortinellus 5

Pluteolus 47

Crepidotus 53

Pluteus 29

Deconica 69

Psalliota 57

Eccilia 33

Psathyra 67

Entoloma 32

Psathyrella 81

Eomycenella 9

Psilocybe 66

Flammula 51

Rozites 37

Galera 49

Russula 16

Gomphidius 79

Schizophyllum 18

Hebeloma 41, 48

Schulzeria 11

Heliomyces 18

Stropharia 60

Hiatula 9

Tricholoma 14

Hygrocybe 10

Trogia 18

Hygrophorus 7, 10, 15
Hypholoma 59

Tubaria 51

Volvaria 20

Inocybe 48

Xerotus 18