JACKSON: UREDINALES OF OREGON 201 
betically under each family and the species similarly under the genus. 
The host plants are also arranged alphabetically under each species. 
No attempt has been made to give a full list of synonyms. In 
general, however, sufficient synonymy is given to show the origin of 
the specific name used as well as any names which have been in general 
use. For convenience of reference the specific nomenclature used is 
that in use in this laboratory, and in general conforms to that used in 
the ‘‘ North American Flora.’’ For similar reasons the generic nomen- 
clature follows that proposed by Dr. Arthur, for use in the “ North 
American Flora,’ except that Melampsora, Puccinia and Uromyces, 
are retained. In order to follow this system consistently it has been 
found necessary to establish a number of new combinations. 
Under each host is given a list of the specimens examined, with 
locality, county, date and collector, followed by the collector’s number. 
Numbers between 1000 and 3450 refer to collections in the Oregon 
Agricultural College Herbarium, if made by members of the botanical 
staff or by students. If no collector is given it may generally be 
assumed that the collection was made by the writer. In order to 
prevent unnecessary repetition, Benton County is not cited following. 
collections made at Corvallis and Philomath. Similarly Hood River 
County is implied for all collections from Hood River or Mt. Hood 
and all collections made at Portland are from Multnomah County. 
The writer is under great obligations to all those who have contrib- 
uted specimens for study and especially to those whose names have 
been mentioned previously. He is also greatly indebted to those 
botanists who have given so generously of their time in determining 
host plants. Dr. A. S. Hitchcock and Mrs. Agnes Chase have named 
most of the grasses. Dr. Theo. Holm and Dr. K. K. Mackenzie 
have each determined a considerable number of species of Carex. 
Dr. C. R. Ball has named most of the willows. Dr. F. V. Coville and 
Dr. K. M. Wiegand have each determined several specimens of Juncus. 
Mr. Paul Standley has determined a large number of specimens from 
miscellaneous families. 
Dr. J. C. Arthur and his former associates very kindly determined 
a considerable number of specimens of the rusts occurring on grasses 
and sedges, and verified the determinations of others, which the writer 
sent from Oregon at various times during the period when the col- 
lections were being made. The greater part of the collections recorded, 
however, have been worked over since the writer took charge of the 
work of this laboratory. During this period it has been his privilege 
to be able to consult freely with Dr. Arthur and to have the unre- 
stricted use of the collections, catalogues, and manuscript notes on 
the rusts, which have been accumulated at the Purdue University 
