PREFACE. 
xi 
Dr. Suckley reached Fort Steilacoom near the end of January, 1856, and remained in active service 
among- the Cascade Mountains of Washington Territory for a year, collecting numerous specimens in all 
departments of nature. Unfortunately, several of the most valuable boxes of specimens sent by him 
from the Territory never reached Washington. 
Resigning his commission in February, 1851, he sailed for China, via San Francisco, collecting sev- 
eral additional sea-birds, here described, on the way. He thus spent three years and one month in the 
field of exploration, of which four months only were occupied east of the Rocky Mountains. During 
the present year he has crossed tlie continent again by laud, via Salt Lake, to San Francisco. 
Dr. Cooper spent two years and three months in Washington Territory and six weeks in California. 
In 1857 he accompanied an expedition through Kansas and Nebraska, as far as Fort Laramie, and has 
combined in this report many observations collected between June and November in those territories. 
Many valuable specimens from Cape Flattery have been furnished by Lieut. Trowbridge, U. S. A., 
and from Astoria, 0. T., by his assistant Mr. Wayne. 
The interesting notes and specimens contributed by Mr. George Gibbs, the able geologist of the 
western division, were collected during several years' journeys and residence at various points. In 
1849 he crossed the continent by the usual emigrant route along the Platte and Snake Rivers. Going 
to California, he spent two years among the mountains in the north of that state and in southern Oregon, 
near the Klamath. In 1853, after some months' residence at Astoria, 0. T., he joined the party under 
Capt. McClellan, and after its return to the west coast made important explorations in company with 
Gov. Stevens around Puget Sound, the Straits of Fuca, Cape Flattery, and the Chehalis River. He still 
continues his investigations and collections as geologist of the N. W. Boundary Survey, together with 
Dr. C. B. R. Kennerly, whose recent discoveries in the Natural History of those remote regions, have 
been of great assistance in the determination of many facts here recorded. 
The very extensive and valuable collections made by Dr. F. V. Hayden, Naturalist to tlie Expeditions 
for the Survey of Nebraska ever since the year 1854, have been also liberally used, and some new 
species collected by him are here described. 
Besides the gentlemen above mentioned as assisting in the collection of materials, the authors are 
indebted to numerous members of the Expedition, and to many citizens of the territories explored, for 
assistance in collecting specimens and observations. The names of such would form too long a 
catalogue for insertion here, but are mentioned in the notes connected with their contributions. 
It has been the object of the authors to present such a report as would be both interesting and 
instructive to the public at large, divested of all such technicalities and discussions as, though 
eminently important and necessary for the establishment of natural science on a true basis, are yet dry 
to the general reader, and unimportant to their present purpose. At the same time they believe that 
through the completeness in this respect of the general reports referred to, but few technical errors will 
be found to have crept in. The references to American authors on the subjects mentioned are very 
complete, and the reader will thus find means of farther information on the more abstruse points 
referred to. 
They have paid attention particularly to the perfection of those portions relating to Washington 
Territory, both because more novelty and interest is connected with the productions of that country, and 
because their residence there of several years each enabled them to collect much more than they could 
on other parts of the route. Still, most of the specimens collected in other territories are mentioned, 
especially such as are of new species. 
Though the natural products already known or believed to occur in the territories mentioned, are 
