with some remarks about the Classification of the Diptera. 73 



and cells completely disguise the original type from which such ve- 

 nations were derived. The best course to pursue, in such cases, is 

 first to determine the section to which the species belongs, by means 

 of the formula of spurs and empodia. This being done, as every 

 section lias its own type of renation, the homologies between the 

 typical and the intricate forms will, in most cases, be easily traced. 

 Of course exceptions will occur here as anywhere eise. 



The crucial test, and at the same time the triuniph, of the spurs and 

 empodia as index-characters were reached when I received for the first 

 time a specimen of Chionea, a two-winged insect without any wings, 

 looking more like a spider, and which, for half a Century, was a puzzle 

 for classificators. Dalman, the discoverer (Act. Holm. 1816andAnalecta 

 1823) referred Chionea to the Tipulariaei), in the sense of Latreille 

 (1809), Fallen and Meigen, that is, of our Nemocera Latr.( 1817). He 

 did so, very probably, on account of the antennae, which are more or less 

 filiform, although only 6-jointed. In the Analecta Dalman describes the 

 ovipositor, the structure of which, if he had been aware of the value 

 of this character, might have induced him to place Chionea among bis 

 Tipularia te r r i co 1 a, Latreille (Farn. Natur. 1 825, p. 484) places 

 Chionea among bis Tipularia terricola; Macquart (S. ä B. 1834) 

 does the same, butboth without giving any reason. Westwood (Introd. 

 II, p. 525, 1840), always accurate, follows suit, placing it among the 

 „Tipulides Macq. (Terricoles Latr.)" and adds, in a foot-note: „My 

 specimen is a female, with an ovipositor like a Tipula." Here, for the 

 first time, the reason of the location among the Tipuli dae is given. 

 Zetterstedt (Dipt. Sc. XI, p. 4255, 1852) forms a family Chioneidae, 

 and, as if to separate it as much as possible from the Tipulidae, 

 places the Mycetophilidae between them. In Walker (Ins. Brit. 

 Dipt. III, p. 268, 1856) Chionea is placed among the Tipulidae. 

 Loew (Monogr. N.-Am. Dipt. I, p. 11, 1862) places it with Dioea 

 among the anomalous Tipulidae. In S ch in er (Fauna etc. II, p. 573, 

 1864) it is treated as an annex to the Tipulidae („als Anhang"). 



Nobody has attempted to investigate the affinities of Chionea any 

 further, although the decisive characters were already predetermined 

 in my formula of 1859 (comp, above), long before I had examined 

 any specimen of this genus. Chionea has no spurs at the tip of the 

 tibiae: that restricts the choice between the sections Limnobina 

 and Eriopterina. Chionea has very distinct pulvilli; this settles 



i) The family-name Tipulidae, in our present sense, appears for 

 the first time in Macq.. Dipt, Exot. I, 1, p. 24 and 38 (1838). Until 

 then, the family was called Tipulariae rostratae by Meigen and 

 Tipularia terricola by Latreille and Macquart (in 1834). 



