The veiled species of Hebeloma in the western United States / Alexander H. Smith, Vera Stucky Evenson, and Duane H. Mitchel.

Introduction

19

season to season, and the sharp difference caused by topography on
the general features of the vegetation, which of course are reflected in
the local mushroom populations, we as yet have no way of predicting
when the "right" season for a particular genus will occur in any given
locality. Our knowledge of a given area relative to its mushroom flora
is advanced piece by piece by those who can take advantage of the
seasons as they occur. The present contribution is an example of this
"piece by piece" procedure.
Extralimital Species. The extralimital species from the Great
Lakes and northeastern United States are included in the main keys
but are designated by a letter within parentheses following the name,
for example, H. affine (a). These species are numbered at the end of
the treatment of the western species as a continuation of the same
series of numbers in the text. Hence the appendix is a continuation of
the text.
Color Terminology. In the descriptions, color names within quotation marks are taken from R. Ridgway (1912) and were matched
with the color sample indicated by the name and under conditions of
full daylight. If conditions for accurate color comparison did not prevail, but the Ridgway name is used, quotation marks around the name
are not used. "Cinnamon-Brown" means the color was matched under
good light conditions. Cinnamon-Brown (without quotation marks) indicates that an actual critical comparison with the color plate was made
but is only a close approximation of the color plate of the color involved. In this context, Ridgway names are often used throughout the
text, and are the basis of all of Smith's color nomenclature for descriptions of taxa unless indicated otherwise. When not capitalized, the
names of the colors are to be interpreted broadly but still approximate
the Ridgway terms.
Formulae
The following chemical reagents were used in this investigation in
addition to tap water as a mounting medium:
1. Melzer's reagent: KI........................... 1.5 g
12...........................0.5g
H20...........................20.0 g
Chloral hydrate................. 22.0 g
A dark violet to blue or bluish gray color change is termed an
amyloid reaction. A dark dull red-brown reaction is designated as dextrinoid. No color change is termed a nonamyloid
or inamyloid reaction.
2. KOH (for reviving dried tissues): 2.5 percent aqueous solu