499 



Tylospilus acutissimus '; 283 



Uhler, P. E., letter to Dr. Hayden 266 



list of Hemiptera of the region west of the Mississippi River 269 



Uncompahgre River 168 



fall of, from divide between it and Mineral Creek 149 



Mountain 166 



Unio luteolus 140 



UnionidsB 140 



Ute Mountain 26 



Peak 199 



Vallecito Creek 185 



fall of, from divide between it a nd Rio Grande 148 



Valvata sincera 126 



virena 126 



ValvatidsB 126 



Velia armata 334 



Veliidse 334 



YertigininsB 128 



Vertigo californica 128 



corpulente 128 



Viburnum marginatum 380 



platanoides 387 



rotundifolium 368 



Wymperi 369 



Vitrinse 128 



Vitrina limpida 130 



Pfeiiferi 130 



Volcanic rocks 151, 152 



Vorticifex Tryoni 138 



Washakie group 407, 409 



White Earth Creek 152,153,166 



Widdringtonia complanata 366, 378 



Williarus, S. G., notes on geology 249 



Wilson, A. D., means of communication between Denver and San Juan mines.. 145 



Mount 163,167,197 



Xnthus auriculatus 296 



Yreteva lode 160 



Zaitha flumiuea 338 



fusciventris 338 



Zamiostrobus ? mirabilis 383 



ZapodidsB 253 



Zapus Hudsonius 254 



description of 255 



geographical distribution 261 



history of 261 



some accounts of, &c., by Dr. Elliott Coues 253 



Zelius bilobus 327 



Zicrona cuprea 282 



Zonites at boveus 128 



Bre weri 129 



couspectus 129 



fnlvus 129 



indeutatus 129 



minnsculus 129 



nitidiis 129 



viridnlns - 129 



Whitueyi 129 



Zophcessa cousocia 274 



porosa 274 



