206 Palaeozoic Fossils of the Northwest — Bierhauer. 



ward condeiisatioQ and conservation of the primitive terrestrial shell. 



The details of world growth cannot be set forth in a page. It 

 is enough to here portray, in few and simple lines, a hypothetic 

 conception of the general process, chiefly to show that while the 

 unequal cooling of land and sea bottom may be altogether inade- 

 quate to produce directly the grand inequalities of the earth's sur- 

 face, the cause has operated cumulatively and in conjunction with 

 the most potent agencies of geology throughout the whole of ge- 

 ologic time, and may be amply adequate to produce indirectly the 

 obscure antecedent stresses (for which adequate cause has not 

 hitherto been assigned) by which the terrestrial motor has ever 

 been kept in motion and to initiate the consequent movements by 

 which the mountains and the lesser valleys have been developed. 

 Thus may a mite be contributed toward the elucidation of the great 

 remaining mystery of geology. 



June 11, 1888. 



lPape7' Z.'] 



A CHECK-LIST OF THE PALAEOZOIC FOSSILS OF WISCONSIN, MINIsTE- 



SOTA, IOWA, DAKOTA AND NEBRASKA. — Bruno Bierhauev. 



It is the object of the following list to enumerate as far as pos- 

 sible all the described fossils of the Palaeozoic formations of Minne- 

 sota, Wisconsin, Iowa, Nebraska and the Dakotas. In none of the 

 states named, with the exception of Wisconsin, has a complete list 

 been made of the known fossils within its borders. The descriptions 

 of the forms enumerated in this list are scattered through the pub- 

 lications of various scientific societies throughout the world, the re- 

 ports of many scientific surveys, home and foreign periodicals, etc., 

 so the work of collating was a very tedious one. In the preparation 

 of the list the compiler received valuable aid from Messrs. E. 0. Ul- 

 rich, Charles R. Keyes,W. H. Scofield and Professor C. W. Hall, and 

 to the first named of these gentlemen are especial thanks due for ac- 

 cess to manuscript lists and compilations not elsewhere obtainable. 



In the classification it will be seen that no one authority has 

 been followed. The general outline is that of Nicholson and Lyd- 

 deker; special groups are arranged according to the plan of some one 

 especially eminent in their study. The Crinoidea are classed closely 

 after Wachsmuth and Springer's revision, the Blastoidea after Eth- 

 eridge and Carpenter, the Cystids after Zittel, and the Bryozoa after 

 Ulrich. The list is designed to be what it is named, a check-list. 



