VI CONTENTS. 



Page. 

 Diecussiou of evidence of the altitudes of various points in tiie United States 

 and Canada — Continued. 



Elevation of Indianapolis 645 



Elevation of the Saint Louis directrix 646 



Elevation of Omaha 648 



Elevation of Kansas City 650 



Elevation of Denver, Colo 652 



Elevation of Chejenne 653 



Elevation of Golden directrix '. 653 



Elevation of O^den, Utah 653 



Elevation of Colorado Springs 654 



Elevation of Pike's Peak 654 



Elevation of Mount Lincoln and Fair Play 654 



Elevation of points on the Ohio Eiver 655 



Elevation of Cairo 656 



Elevation of points determined in this investigation 657 



Topographical report of Middle Park division, 1873. By S. B. Ladd, M. E 661 



Oeographical report of Henry Gannett, M. E '. 670 



[General report.] 670 



Princii>al passes in the high mountains 675 



Means of communication 675 



Principal wagon-roads and trails : 676 



Botanical notes 677 



Jiypsometrical 678 



APPENDIX. 



Gold Hill mining-region; its position and general geology. By Arch. E. Mar- 

 vine 685 



The telluride ores of the Bed Cloud and Cold Spring mines. Gold Hill. By B. 



Sillimau 688 



LIST OF NEW SPECIES DESCEIBED. 



IPOSSIL plants: 



Woodwardia latiloba 391 



Pteris affinis 392 



Pteris subsimplex 392 



Pteris Gardneri 393 



Aspidium Goldiauum 393 



Sphenopteris membranacea 394 



Sphenopteris nigricans 394 



Hy menophyllum confnsum 395 



Selagiuella Berthoudi 395 



Equisetum(?) Itevigatuni 395 



Flabellaria (?) fructifera 396 



Eriocaulon (?) porosura 396 



Zingiberites (?) undulatus 396 



Ehizocaulou gracile 396 



Qnercus Goldianus 398 



Quercus Cleburni : 399 



Ficus zizyphoides 399 



Ficus truncata 400 



Platanus rhomboidea 400 



Pisouia racemosa 400 



Viburnum Lakesii 401 



Cornus Holmesii 402 



Nelumbium tenuifolium 402 



Nelunibium Lakesiauum 403 



Zizyphus distortus 404 



Ehamuus inequalis 405 



Platanns dubia 406 



Laurus sessilillora 407 



Persea Brossiana , 407 



Cornus impressa 408 



Salvinia cyclophylla ^. 408 



Lycopodiuni prominens 409 



Eqnisetum Wyomiugonse 409 



Aeorus aftiLis 410 



