X T E . 



Six volumes, accompanied l>y one topographical and one geological 

 :itl;is. embrace Reports of Explorations and Surveys West ot' the One hund- 

 redth Meridian up to the close of the field-season of 1873, (excepting Vol- 

 ume V, which embodies results up to 1874,) as follows: 



Volume I. Geographical Report. 



Volume II. Astronomy and Meteorology, including Barometric Alti- 

 tudes. 



Volume III. Geology and Mineralogy. 



Volume IV. Paleontology. 



Volume V. Zoology. 



Volume VI. Botany. 



An advance edition of the Topographical Atlas, consisting of Title- 

 Pa ge, Legend-Sheet, Index, Progress and Basin Maps, and sheets Nos. 4D, 

 50, 57, 58, 59, 65, 66, and 67, was i-sued in 1874 ; other sheets will follow as 

 rapidly as they can be prepared, engraved, and printed. The maps from 

 the field-work of 1873 and subsequent years will be projected upon a scale 

 of one inch to four miles. Sheets of a geological atlas, to supplement 

 Volume III, based upon the topographical results, advance toward com- 

 pletion. 



Addenda Note. Lieutenant Wheeler, in his Annual Report for 1875, 

 ivi-oinnicnds an additional volume, to be numbered VII, and to be devoted 

 to the subjects of Ethnology, Philology, and Ruins. 



