iisroEX. 



Page. 



Acmaea occidentalis 463 



ActJBonina ? subelliptica 463 



• Actceon concinnus 463 



subollipticus 463 



Ago of the igneous rocks 219 



Agraulus sp. ? 460 



owodI 342 



A gricultural lands 314 



Agricultural resources of the Sioux Keservation 5 



from Cheyenne to Fort Laramie 23 



Akera glans-oryza 437 



Allen, Sir. Janios, cited 252 



Allen, Mr. John W., cited 252 



Altitudes and positions 551 



Aniauropsis paludinajformis 431 



Ammonites conradi 464 



cordatus 379 



cordiformis 378 



var. distans 380 



dans 464 



henry i 461 



nehrascensis 464 



placenta 464 



serrato-carinatus 440 



wyomingensis 440 



Amphibious Creek, [271 478 



[204] 473 



[205] 472, 474 



[212] 475 



goldon 235 



Anchura (Drepanocheilus) nebrascensis 429 



.' suble V i s 428 



Ancyloceras jenneyi 452 



nebrasccnse 451 



tricostatum 454 



? imcimi 464 



Andesite 483 



augite 483 



hornblende 483 



Anisomy on alveolus 432 



borealis 436 



patelliformis 435 



subovatus 433 



A utecedent drainage 216 



Apatite in sanidin 507 



sanidin-trachyte 512 



trachyte 491,519 



ApetalsB 536 



Page. 



Aphrodioa ? tenuis 462 



Aporrhais biangulata 427 



meeki 426 



nebrascensis 429 



newberryi 425 



snblevata 428 



sublevjs 428 



(Drepanocheilus) nebrascensis 429 



(Goniocheilus) castorensis 427 



Area inomata 359, 405 



shumardi ^. . . . 405 



Archaean formations, correlation of . . 63 



gold from the 50,54 



history, summary of 220 



island 214 



of Canada 45 



Castle Creek districl 262 



Kawhide Butte 27 



the Appalachian Mountains . . 47 



BlackHiUs 48 



headwaters of the Niobrara 28 



Rocky Mountains 48 



subdivisions of the, in the Black 



Hills 41,50,63 



system, the 45 



thickness of the 61 



time, history of 62 



topography of the 48, 212 



unconformity in the 62 



ArenicoUtes, sp.? 333 



Assays of gold quartz 294 



Astarte evansi 413,417 



?fragilis 363 



inomata 368, 400 



Asterias ? dubium 344 



Astronomical work 543 



Avelana concinna 463 



subglobosa 463 



Avicula curta 354 



linguiformis 384 



1 fibrosa 386 



nebrascana 385 



(Monotis) tenuicostata 354 



(Oxytoma) mucronata 357 



Audubon, exploration by 7 



Augite-trachj-t« 489 



AxioUte 485 



Bach, Leopold von, cited 7 



557 



