636 A CENTURY OF PROGRESS IN THE NATURAL SCIENCES 



nomic rank. In 1885 E. F. von Homeyer (b. 1809, d. 1889) included the wood- 

 peckers, nuthatches, creepers, and hoopoes in the same order, an arrangement 

 similar to that used by Willughby more than two hundred years before! As 

 late as 1893, Anton Reichenow (b. 1847, d. 1915) indicated his belief that a sys- 

 tem of classification should be a means of identification and no more. 



The careful work of Fiirbringer and Gadow did much to overcome these 

 viewpoints. In 1898 Frank E. Beddard (b. 1858, d. 1925), who had followed 

 in the footsteps of Garrod and Forbes, published his volume on the structure 

 and classification of birds, which brought together a great amount of the ana- 

 tomical evidence for the arrangement of orders and families. 



Descriptive anatomy languished somewhat after the turn of the century. In 

 the United States Robert W. Shufeldt (b. 1850, d. 1934) continued to describe 

 the osteology of birds and in England William P. Pycraft (b. 1868, d. 1942) 

 produced an impressive series of anatomical papers. 



In recent years the studies by George E. Hudson, Fred H. Glenny, and 

 William J. Beecher have been directed toward the clarification of classification 

 through anatomical research. Hudson has published (1937, 1948) studies on the 

 muscles of the pelvic appendage; Glenny, beginning in 1940, has produced a 

 series of papers on the main arteries in the region of the heart; and Beecher 

 (1950) used the bill and jaw musculature to furnish evidence of convergent 

 evolution in the American orioles. Other recent research has been concerned 

 with the interpretation of functional and adaptational anatomy rather than its 

 utilization in classification. The work of W. H. Burt (1930) on woodpecker 

 adaptations, M. Stolpe (1932) on the hind limb, A. H. Miller (1937) on the 

 Hawaiian goose, W. L. Engels (1940) on adaptations in the thrashers, F. Rich- 

 ardson (1942) on tree-trunk foraging birds, H. I. Fisher (1946) on the New 

 World vultures and William J. Beecher (1951) on the American blackbirds, are 

 examples of this trend. 



Bird Migration 



It was within the last half of the eighteenth century that the belief that 

 some birds hibernated in the muddy bottoms of ponds and lakes was finally 

 discredited. With the general acceptance of the fact that birds did actually 

 migrate there came a wave of speculation as to the methods, routes, and signifi- 

 cance of the migratory movements. Precise data based upon observations were 

 few at first but gradually a body of reliable information was accumulated. 

 Among the first reliable data were records of the arrival and departure of mi- 

 gratory species at a particular location. In 1828 Hermann Schlegel had specu- 

 lated upon the routes and places of winter residence of European birds and the 

 Swedish ornithologist Ekstrom had published the first arrival and departure 

 dates of migratory species. In 1853, Karl E. Kessler, a professor at the Univer- 

 sity of Kiev, published the arrival and departure dates for a number of species 

 at various localities in western Russia and compared the dates with temperature. 

 In spite of these records of actual field observation, most of the investigations 

 into migration were conducted from a desk. J. A. Palmen (b. 1845, d. 1919), a 

 Finnish scholar, proposed a theory of ''fly^^^ays" in 1876. He believed that there 

 were nine narrow migratory lines which were followed by European and Asiatic 



