580 A CENTURY OF PROGRESS IN THE NATURAL SCIENCES 



and scattered. There was not one in the United States except the small Harris col- 

 lection in Boston. In Europe, the leading collections were in London, Oxford, 

 Paris, Leningrad, and Vienna. This neglect of the order was destined to be 

 changed in an almost dramatic manner following the arrival in America in 1856 

 of Baron Osten Sacken, "Father of American Dipterology," who served as Sec- 

 retary of the Russian Legation in Washington until 1862, and as Russian Con- 

 sul General in New York from 1862 to 1871. Osten Sacken himself was one of 

 the most accomplished students of the order, but served an even more important 

 function in providing ample materials of North American Diptera for the study 

 of Hermann Loew, outstanding systematic dipterologist of the period. Loew de- 

 scribed as new some 1,350 species of North American Diptera, chiefly in a series 

 of ten reports, or centuries (1861-1872), each including one hundred species. 

 The combined Loew-Osten Sacken collections, now preserved in the Museum of 

 Comparative Zoology in Cambridge, Massachusetts, comprise the most important 

 basic series of flies in America. 



Other outstanding European students of Diptera who were most active dur- 

 ing this period included Becker, Bellardi, Bergenstamm, Bergroth, Bigot, Bons- 

 dorff, Brauer, Dziedzicki, Egger, Gerstaecker, Giglio-Tos, Girschner, Jaennicke, 

 Karsch, Kowarz, Lioy, Meade, Mik, Pokorny, Portschinsky, von Roder, Rondani, 

 Riibsaamen, Schiner, Schnabl, Stein, Strobl, Winnertz, van der Wulp, Zeller, 

 Zetterstedt, and various others. The outstanding major works of this group in- 

 cluded Brauer und Bergenstamm 's Die Ziveiflilgler, 7 parts (1880-1894), Ron- 

 dani's Dipterologiae Italicae Prodromus, 8 volumes (1856-1880), Schiner's 

 Fauna Austriaca, Diptera (1862-1864), and Zetterstedt's Diptera Scandinaviae, 

 14 volumes (1842-1860). 



In North America, in addition to the work of Loew and Osten Sacken, this 

 period marked the initial activity of Coquillett, Johnson, and Williston. Lead- 

 ing workers in South America included the Lynch Arribalzagas and Philippi 

 (1865). In Australia, a most outstanding figure was Skuse, whose eight princi- 

 pal papers on the Diptera of Australia (1888-1891) are of unusual importance. 

 Virtually all other taxonomic work on exotic Diptera was accomplished by stu- 

 dents in America and Europe, including Bellardi, Schiner, and van der Wulp. 



In the fields of dipterous morphology, phylogeny, and biology noteworthy 

 advances were made. The science of chaetotaxy was proposed and developed by 

 Osten Sacken (1881), although the term "machrochaeta" had been suggested 

 many years before by Rondani (1845). A major landmark was attained in 1883 

 when Brauer first demonstrated the importance of the larva in classification and 

 used the nature of emergence from the pupa to furnish the primary division of 

 the order into Orthorrhapha and Cyclorrhapha. Weismann (1864) published 

 an outstanding paper on dipterous development. Our state of knowledge of 

 embryology was indicated by Korshelt and Heider (1890-1892). 



Pioneer work on the venation and morphology of the wing was accomplished 

 by Adolph (1879), Amans (1885), Cholodkowsky (1886), and others. Loew and 

 Schiner proposed their respective systems of venation in 1862. Significant work 

 on the morphology of individual dipterous types was done on the blowfly by 

 Hammond (1881) and Lowne (1890-1895). 



The earliest work on fossil Diptera began at this time with the appearance 

 of Loew's paper on the Amber Diptera (1850). He was followed by several 



