148 



SCIENCE 



[N. S. Vol. XXXII. No. 813 



professor and a scientific writer, especially 

 upon geology and paleontology. 



While he was practising medicine at Iowa 

 City he was appointed state geologist of Iowa 

 by legislative enactment, and he assumed the 

 duties of that office in April, 1866. He con- 

 ducted that survey until 18T0, when two vol- 

 umes of reports were published, devoted mainly 

 to structural and economic geology. The 

 work was then suspended for want of legisla- 

 tive appropriations. 



In 1866 he received the degree of master of 

 arts from Iowa College at Grinnell. 



In 1867 he was appointed to the professor- 

 ship of natural history in the Iowa State 

 University, with the understanding that he 

 should perform only a part of the duties of 

 that chair during the continuance of the sur- 

 vey, and at its close assume the full duties of 

 the same. 



He became a member of the American As- 

 sociation for the Advancement of Science in 

 1868, and a feUow, when fellowships were first 

 established by the association. 



He closed his work upon the Iowa survey 

 in 1870, when he assumed the full duties of 

 his professorship in the university. These 

 duties he continued to perform until 1873, 

 when he was called to a similar chair in Bow- 

 doin College, which call he then accepted and 

 removed with his family to Brunswick, Maine. 



In 1874, at the request of Major (then 

 Lieutenant) G. M. Wheeler, he undertook the 

 publication of the invertebrate paleontology 

 of the government survey west of the one- 

 hundredth meridian, then under his direc- 

 tion. He prosecuted this work in connection 

 with his duties at Bowdoin College until the 

 next year, when he resigned his professorship 

 and removed with his family to Washington, 

 and joined the TJ. S. Geological Survey of the 

 Eocky Mountain Region, in charge of Major 

 J. W. Powell. 



In 1876 he joined the U. S. Geological Sur- 

 vey of the Territories in charge of Dr. F. V. 

 Hayden and remained with it until its sus- 

 pension in 1879. He was appointed curator 

 of paleontology in the U. S. National Museum 

 in 1879, and geologist to the reorganized U. 



S. Geological Survey in 1882. In the latter 

 year he was detailed to act as chief of the 

 Artesian Wells Commission upon the Great 

 Plains, under the auspices of the TJ. S. De- 

 partment of Agriculture, upon the completion 

 of which duties he returned to his work upon 

 the survey and at the museum. 



In 1882 he was commissioned by the direc- 

 tor of the National Museum of Brazil to pre- 

 pare for publication the Cretaceous inverte- 

 brates which had been collected by members 

 of the Geological Survey of that empire. The 

 results of this work were published at Rio de 

 Janeiro in both Portuguese and English. 



He was president of the Biological Society 

 of Washington for the years 1883 and 1884, 

 and vice-president of the American Associa- 

 tion for the Advancement of Science in 1888. 



He continued a member of the TJ. S. Geo- 

 logical Survey until 1892, when he resigned. 



The degree of LL.D. was conferred upon him 

 by the State University of Iowa in 1893. 



He WIS one of the founders of the Geolog- 

 ical Society of America. 



He was elected to corresponding member- 

 ship in the following academies and scientific 

 societies : The Academy of Natural Science 

 of Philadelphia in 1880; the Geological So- 

 ciety of London in 1893 ; Isis Gesellschaft 

 fiir Naturkunde, Dresden, Saxony, in 1893; 

 the R. Accademia Valdarnese del Poggio, 

 Montevarchi, Italy, in 1893; the k. k. Geolo- 

 gische Eeichsanstalt, Vienna, Austria, in 1893 ; 

 the Kaiserliche Leopoldinisch-Carolinisch. 

 Deutschen Akademie der Naturforscher, Halle, 

 on the Saale, 1894. 



In 1895, he was appointed a scientific asso- 

 ciate of the Smithsonian Institution. 



On December 20, 1899, he was elected for- 

 eign member of the Geological Society of 

 London. 



The titles of his many papers are too nu- 

 merous to be given here but an annotated 

 list of them was published in Bulletin 30 

 of the U. S. National Museum in 1885, a 

 continuation of it in the Proceedings of the 

 same, Vol. XX., in 1897, and the present 

 list contains ten additional entries, making 

 220 in all. These titles being arranged 



