IV 
TABLE OF CONTENTS 
Ezra T. Cresson. The extracts from the letters of the latter, 
reproduced by me, afford an interesting insight into this remark¬ 
able instance of American enterprise and energy. 
VI Winnertz and Loew .44 
A notice on the meritorious dipterologist Job. Winnertz, and an 
account of the extraordinary injustice of Loew towards him. 
VII Remarks, Historical and Critical, concerning Loew’s first 
Volume of the “Monographs of North American Diptera” 
Washington, 1862 . 47 
I show' that, after more than twenty years of descriptive work 
on Diptera, Loew found himself utterly unprepared to formulate 
his general views on the terminology, as well as on the systematic 
distribution of the families of this order. The very natural re¬ 
quest of the Smithsonian Institution to have some “ Introduction to 
Dipterology ” placed at the head of the intended series of “ Mono¬ 
graphs ” filled him with fear and terror (“ Furcht und Grauen”). 
The families in the volume are arranged most arbitrarily. Loew 
was convinced that the principal subdivision of Diptera in Nemo- 
cera and Brachi/cera must be given up, and if he did not at once 
introduce this innovation into the volume, it is merely because he 
felt repugnant to deviate too much from the accepted arrange¬ 
ment (“ urn nicht zu sehr von dein Gew'ohnten abzuweiehen ”; in 
a letter to me dated July 25, 1860. Compare, in the “Introduc¬ 
tion,” p. 10 at bottom, and p. 11). 
VIII Haliday and Loew .51 
An account of the relations of these two eminent entomologists 
and an attempt at a characterization of Haliday as a dipterologist. 
To this Chapter is added a portrait of Mr. A. II. Haliday (the first 
ever published). 
IX On Loew’s Work on Amber Diptera in general, and on the 
Circumstances of its ultimate Failure.63 
The fossil Diptera enclosed in the lumps of Amber abundantly 
found on the Baltic coast of Prussia have always been one of the 
favorite objects of Loew’s study. His first essay : “ Ueber den 
Bernstein und die Bernsteinfauna,” Berlin, 1850, was but an im¬ 
perfect attempt to bring these fragments of an extinct fauna into 
agreement with the systematic distribution of recent Diptera. Ilis 
lecture, “ Ueber die Dipteren-Fauna des Bernsteins,” 1860, an Eng¬ 
lish translation of which was published by me in Silliman’s Jour¬ 
nal in 1801, contains an abstract of results, and very interesting 
generalizations on the same subject. The dream of his life was 
the publication of a general work on Amber Diptera which he had 
conceived on a large scale, for which he had drawn a number of 
plates, and must have prepared a great deal of letter-press. This 
intended publication has never taken place. My long intercourse 
with Loew has enabled me, in the above-quoted chapter, “ to 
throw some light on this otherwise very obscure subject.” 
