The following paper on the Diptera of the Expedition, by D. W. 

 Coquillett, Division of Entomology, U. S. Department of Agriculture, 

 was originally published in the Proceedings of the Washington Acad- 

 emy of Sciences, vol. ii, pp. 389-464, Dec. 7, 1900. It is here 

 reprinted from the same electrotype plates, so that it may be quoted 

 exactly as if it were the original. The original pagination has 

 been preserved and transferred to the inner or hinge side of the page, 

 where it is enclosed in brackets, thus [390] ; while the consecutive 

 pagination of the present volume has been added in the usual place. 

 The present headpiece and title have been substituted for the running 

 heading of the Academy's Proceedings and the original title, which 

 was : Papers from the Harriman Alaska Expedition, ix. Ento- 

 mological Results (3): Diptera. No other alterations have been 

 made. 



Since the original publication of this paper the author has described 

 as new, under the name Siinulium fulvum, the species here (p. 7 

 [393]) referred to S. ochraceum Walker. (See Proc. U. S. Nat. 

 Mus., XXV, p. 96, 1902.) 



The author desires to record the following additional corrections : 



Page 5 [391 ] : 



Eighteenth line from bottom, enclose ' Meigen ' in parentheses. 



Seventeenth line from bottom, for ' Anaclinia' read Mycetophila, 

 Page 8 [394] : 



Twelfth line from bottom, enclose ' Linn^' in parentheses. 



Eleventh line from bottom, change ' Scatopse ' to Tipula. 

 Page ID [396] : 



Eleventh line from bottom, enclose ' Fabricius ' in parentheses. 



Tenth line from bottom, change ' Ceratopogon ' to Chironomus. 

 Page 13 [399], fifth and fourth lines from bottom, change 'disphana' to 



diaphana. 

 Page 19 [405], fom-th line from bottom, for ' Pachyrrhina' read Pachyrhina. 

 Page 20 [406] : 



First line, for ' Xylophagidae ' read LeptidcB. 



Sixteenth line from bottom, for ' Stratiomjiidae ' read StrattomyidcB. 

 Page 21 [407], twentieth line from bottom, for ' Empididae ' read Empidce. 

 Page 55 [441], thirteenth line from bottom, for ' Anthomyiidse' read Antko- 

 tnyidce. 



Editor. ' 



(«) 



