178 The Smithsonian Institution 



the higher the latitude of their place of birth ; that specimens 

 from the Pacific coast are apt to be darker than those from 

 the interior, and that specimens from near the line of junction 

 of two well-marked provinces or regions often show the influ- 

 ence of hybridization. When he comes to discuss migrations, 

 it is in their relations to the laws of the winds of the Northern 

 Hemisphere that he studies them, and concludes that the trans- 

 fer of American birds to Europe is mainly due to air currents. 



He did not himself produce much of this sort of scientific 

 literature, for he had not the opportunity, since at the very 

 period of his career when he was best fitted to make such 

 studies, he had to give almost his whole time and energy 

 to routine administrative duties. "This paper alone," says 

 Billings, "is sufficient evidence of his capacity for general- 

 izing from a series of isolated facts." 



"The two men," continues Billings, "who have exerted the 

 strongest influence upon natural history studies in this country 

 are Louis Agassiz and Professor Baird. In many respects 

 they were very unlike ; circumstances gave them widely 

 different fields, and they worked on different plans and by 

 different methods. They began their public career in this 

 country almost together ; but Agassiz was already famous as 

 the result of seventeen years' incessant work, while Baird 

 was an almost unknown youth. Agassiz was a born teacher, 

 a fascinating lecturer, gifted with eloquence which won its 

 way everywhere ; Baird could only speak freely in the pres- 

 ence of a few, and for the most part taught only by the pen 

 and by example. Each of them created a great museum in 

 spite of many obstacles, the first winning the means largely 

 from private contributions, which were a tribute to his elo- 

 quence ; the second gaining his end more indirectly, through 

 his connection with the Smithsonian Institution and gov- 

 ernment. Each of them gathered around him young men 



