290 LEADING AMERICAN MEN OF SCIENCE 



Silliman, which appeared in the American Journal of Science for 

 March, 1862. 



In the succeeding summer, Marsh refused the professorship 

 offered him by his Alma Mater, and in November, 1862, started 

 on his first European trip, visiting the International Exhibition 

 in London and spending some time in the various museums of 

 England. Later he entered Berlin University as a student of 

 mineralogy and chemistry, under G. and H. Rose, respectively, 

 and of microgeology under Ehrenberg. 



In the spring of 1863, his studies were continued at Heidelberg 

 University, under the direction of Bunsen, Blum, and Kirschoff, 

 and it was during this semester that he became a fellow of the 

 Geological Society of London, his name having been proposed by 

 Sir Charles Lyell. The following summer was devoted to an 

 extended trip through Switzerland, during which a special study 

 of glaciers was made. Returning to Berlin, he began researches 

 in paleontology, a professorship in that branch of science having 

 been instituted for him at Yale College. This subject was dili- 

 gently pursued throughout the academic year, and further prep- 

 arations for his prospective work were made in extensive collec- 

 tions of books and specimens. He again studied at Berlin in 1864 

 under the eminent scholars Beyrich, Peters, and Ehrenberg, and 

 made various excursions to the Hartz Mountains and other parts 

 of northern Germany. Several short papers giving the results of 

 his investigations on invertebrates were presented to the Geo- 

 logical Society of Germany, of which he had then recently been 

 elected a member. The results thus obtained, however, were 

 never fully published, and two brief notes on annelids, another on 

 Ceratites, a description of the fossil sponge Brachiospongia, and a 

 short paper on the color markings of Orthoceras and Endoceras 

 constitute his principal articles dealing with invertebrate fossils, 

 the series closing in July, 1869, with a paper on a new species of 

 Protichnites from New York. This paper virtually ended his 

 miscellaneous contributions to science, and henceforth the study 

 of vertebrate paleontology became his sole aim. 



In the summer of 1864, Marsh made extensive geological explo- 



