VI 



The cranial and dental characters of Geomyidae, by Dr. Elliott Coues, U. S. A. . . 81 



Synopsis of Insectivorous Mammals, by Theodore Gill 91 



Prefatory 91 



Historical - 91 



Monographic essays - 103 



Eange of variation 104 



Geographical relations of American species 106 



Insectivora. 106 



Appendix 113 



I. Contrasted characters of Soricidse and Talpidae... 114 



II. Bibliography 118 



Eeport on the natural history of the United States Geological and Geographical 



Survey of the Territories, 1874, by Ernest lugersoll, zoologist 121 



List of localities from which specimens were brought home 123 



General account of the work 123 



Special report on the Mollusca, by Ernest IngersoU, zoologist 125 



List of authorities - 140 



BULLETIN No. 3. 



Means of communication between Denver and the San Juan mines, by A. D. 



Wilson 145 



Eeport on the mines and geology of the San Juan country, by F. M. Eudlich, S. 



N. D 151 



Eeport on the topography of the San Juan country, by Franklin Ehoda, assist- 

 ant topographer 165 



Ascent of Mount Sneifels 193 



Methods used in determining the elevations of points in the district 202 



Notes useful for the location of miners' monuments in Baker's Park 209 



Notes on some peculiar forms of erosion in Eastern Colorado, with heliotype 



illustrations, by F. V. Hay den 210 



BULLETIN No. 4. 



Notes on the surface-features of the Colorado or Front range of the Eocky Mount- 

 ains, by F. V. Haydea 215 



The Tertiary Physopoda of Colorado, by Samuel H. Scudder 221 



Outlines of a natural arrangement of the Falconidai, by Eobert Eidgway 225 



BULLETIN No. 5. 



A review of the ft)ssil flora of North America, by Leo Lesquereus 233 



Notes on the geology of some localities near Cafion City, Fremont County, Colo., 



. by S. G. Williams 249 



Some account, critical, descriptive, and historical, of Zapus Hudsonius, by Dr. 



Elliott Coues, U. S. A 253 



On the breeding-habits, nest, and eggs of the White-tailed Ptarmigan (Lagopus 



leucurus), by Dr. Elliott Coues, U. S. A 263 



List of Hemipteraof the region west of the Mississippi Eiver, including those col- 

 lected during the Hayden explorations of 1873, by P. E. Uhler 269 



On some new species of fossil plants of the Lignitic formations, by Leo Les- 



quereux '. 353 



New species of fossil plants from the Cretaceous formation of the Dakota group, 



by Leo Lesquereux 39I 



Notes on the Lignitic group of Eastern Colorado andWyoming, by F.V. Hayden.. 401 



On the supposed ancient outlet of Great Salt Lake, by' A. S. Packard, jr 413 



BULLETIN No. 6! 



An account of the various publications relating to the travels of Lewis and Clarke, 

 with a commentary on the zoological results of their expedition, by Dr. 



EUiottCoues, U.S. A '....... 417 



Part I. Bibliographical 417 



Part II. Zoological 430 



Notice of a very large Gouiatite from Eastern Kansas, by F. B. Meek!!'."..'.'.'.'.* 445 



Fossil Ortboptera from the Eocky Moun tain Tertiaries, by Samuel H. Scudder. . . 447 



Studies of the American Falcouid;e, by Eobert Eidgway 450 



