PREFATORY NOTE. 
19 “Synopsis of the Flora of Colorado,” which the survey now pre- 
‘sais to the public, has been prepared by Prof. Thomas C. Porter, of 
_‘avette College, Easton, Pennsylvania, and Mr. John M. Coulter, one 
2 assistants connected with the survey for the past two years. It 
ended to be a type of a series of “handbooks” of different branches 
‘atural history, to be published from time to time as a part of the 
of “Miscellaneous Publications,” for the use of students all over 
ountry. No. 3 of the series is now passing through the press, and 
 >een prepared by the eminent ornithologist, Dr. E. Cones, U. 8. A. 
' Lform an octavo volume of several hundred pages, bringing the 
subject of western ornitholgy up to date. The mountain regions 
lorado are now so accessible to the traveling public, that this - 
sis will prove a most valuable aid to students, and travelers who 
re annually visiting Colorado in great numbers. Indeed, the moun- 
voas portions more nearly resemble the Alpine districts of Central 
sepe, not only in the scenery, but also in the different forms of veg- 
“oon. The tide of travel is fast turning in this direction, and the 
aad for works ot this kind will necessarily be very great. It should 
~ stated here, that the obligations of the survey to Professor Porter, 
» “3 Share in the work, are very much increased from the fact that he 
«ted several months in its preparation without compensation from 
-overnment. 
F..V. HAYDEN, 
United States Geologist. 
 3ICE UNITED STATES GEOLOGICAL AND GEOGRAPHICAL = 
SURVEY OF THE TERRITORIES, January 14, 1874. 
