INTRODUCTION. 11 



(1828-30) appeared. They did not introduce any change in 

 the classification, but added two new genera to the system.: 

 Polymera and Mcgistoccra. 



Macquart, in both 'of his works (Dipteres du Nord de la 

 France, 1825, and Eist. Nat. des Ins. Dipteres, Yol. I, 1834), 

 retains Latreille's designations : Diptera nemocerd and Tipu- 

 larise terrieolde. To the latter family, in the last of the two 

 works, he adds the genus Dixa, placed by Meigen among the 

 Tip. fungicolde. He also follows Latreille in subdividing the 

 Tip. terricolse in the hngipalpi (genera : Pty diopter a, Cteno- 

 phora, Tipula, Paelujrrliina, Nephrotoma, Pedicia) and brevi- 

 palpi (Ozodicera, Bhipidia, Bhamphidia, Idioptera, Limnophila, 

 Limnobia, Cylindrotoma, Symplecta, Erioptera, Polymera, Me- 

 gistocera, Trichocera, Dolichopeza, Dixa, Anisomera, Chionea). 

 Among these genera Ozodicera, Idioptera, Pachyrrliina, Limno- 

 phila, and Cylindrotoma were new. Chionea had been described, 

 in 1816, by Dalman, and correctly referred to the Tipididde. The 

 principal innovation of Macquart w r as the introduction of the 

 genera Pachyrrhina and Limnophila, which broke up Meigen's 

 large genera Tipula and Limnobia. 



The most important publications on the Diptera in general, 

 since Macquart's last quoted works, are Zetterstedt's, Walker's, 

 and Eondani's. Zetterstedt (Fauna Lapponica, 1840, and 

 Diptera Scandinaviae, tenth volume, 1851) introduced several 

 new genera, but did not improve the distribution of the family 

 of Tipulidde. The subdivision into longipalpi and brevipalpi was 

 entirely abandoned by him, and the genera belonging to these two 

 groups were arranged promiscuously. The genus Chionea forms 

 a separate family for itself, between which and the Tipulidee the 

 MycetopHiilidse are inserted. Zetterstedt's new r genera are Psilo- 

 conopa, Dicranota, Tricyphona, all of which had been originally 

 adopted in his earlier work in 1840. 



Walker (Insecta Britannica, Diptera, Yol. Ill, 1856) adopts, 

 in the main, Meigen's distribution of the Tipirtidee. Macquart's 

 genera Limnophila and P 'achy rrhina are introduced as subgenera 

 only. The genera Geranomyia and Ula, originally proposed by 

 Mr. Haliday, in 1833 (Entomol. Magaz. Yol. I), are introduced 

 here, and the genus Amalopis is suggested by the same author in 

 a note (Addenda, p. xv), but not introduced in the body of the 

 work. 



