CLASSIFIC'ATIOX OF AMERICAX WHEAT VARIETIES. 15 
natural and artificial production of new forms, the number of dis- 
tinct varieties of wheat existing in the United States is not sur- 
prising. It is really remarkable to find so comparatively few in com- 
mercial cultivation. By making all possible combinations of the 
characters used by the writers in describing the wheat varieties, 
several thousand new varieties could be produced. 
PREPARING DESCRIPTIONS, HISTORIES, AND DISTRIBUTIONS. 
For each A'ariety there is given the description, the history so far 
as known, the distribution in the United States, and the synonymy. 
PREPARATION OF VARIETAL DESCRIPTIONS. 
Detailed descriptions have been written of the wheat varieties here 
enumerated. These descriptions contain much more detailed infor- 
mation concerning the nature of the varieties than is included in the 
keys and are necessary for a clear knowledge of the appearance of 
the varieties. The descriptions are not complete, however, several of 
the morphological characters of the wheat plant not being included 
because they are of little or no value in classification. Only the more 
important taxonomic characters are used. This has made possible 
shorter and more concise descriptions than would otherwise be 
possible. However, they are thought to be sufficiently inclusive to 
provide a comprehensible knowledge of the different varieties. 
Following the descriptions of many varieties is a paragraph show- 
ing the chief characters which distinguish the variety from closely 
related ones. This gives the reader a more ready comparison of cer- 
tain varieties than is otherwise possible. 
PREPARATION OF VARIETAL HISTORIES. 
The history of the origin of varieties can not be neglected in a 
complete classification, as many varieties are scarcely or not at all 
distinguishable from similar or closely related varieties and differ 
only in their origin or qualities. In this stud}' much attention has 
been given to the history of varieties, and to many readers it proba- 
bly will be the most interesting and valuable part of the classifica- 
tion. The compiling of these histories has been a long and arduous 
task. It has required a review of the literature on wheat varieties 
written during a period of more than 200 years. The sources of this 
information are varied. Definite information is readily available 
on the origin of only a comparatively few varieties. Introductions 
of foreign varieties have been recorded in recent years by the Office 
of Foreign Seed and Plant Introduction. Frequent reference is made 
to the accession numbers and published inventories of that office. 
Many bulletins of the State agricultural experiment stations have 
