104 LEPTIDJE. 



Eyes in tf contiguous for a considerable 



distance ; frons in $ only as broad as [p. 1 til . 



ocellar tubercle .". SURAGINA, Walk., 



8. Frons and side-margins of face (c? $) dis- 



tinctly hairy ATHERIX, Mg., p. 120. 



Frons in tf and side-margins of face (c? $) [? 112. 



bare ATRICHOPS, Verr., 



9. Anal cell open ; hind tibiae with two spurs . . LEPTIS, F., p. 124. 

 Anal cell closed ; hind tibiae with one spur [p. 128. 



only CHRYSOPILUS, Macq., 



Subfamily XYLOPHAGIN^]. 



Face flat, no socketed epistome margined by broad side-cheeks. 

 Palpi long, curved upwards ; the 3rd antenna! joint flagelliform, 

 generally divided by annulations into seven parts, but in Eliaclii- 

 cerus into many more. Eyes in c? distinctly separated, in $ 

 rather wider apart. Body and legs almost bare. Scutellum 

 smaller and metanotum more conspicuous than in normal LEP- 

 TID^E. Abdomen considerably elongated or cylindrical ; the male 

 genitalia rather complex, those of the $ long and telescopic. All 

 tibiae spurred. Wings with auxiliary and 1st veins long, 2nd 

 shorter than in LEPTINJE, 3rd with fork rather short, widely open, 

 lower branch ending above or at wing-tip; anterior cross-vein 

 very short, situated towards base of discal cell ; posterior cross- 

 vein exceedingly short or absent, anal cell normally closed at wing- 

 border ; axillary vein indistinct or absent ; alulae absent. 



Life-history. " Larva amphipneustic, allied to those of C(ENO- 

 MYINJE and LETTING ; carnivorous ; living under the bark of dead 

 trees and preying upon other (probably dead) larvae occurring 

 there, especially those of wood-boring Coleoptera, or upon the 

 debris and detritus left by those larvae" (Verrall). Birch, alder, 

 and pine are the trees mostly favoured. The imagos are usually 

 found about their breeding-places in woods. 



Only one genus of this subfamily (Rhachicerus) occurs in India. 



Xylophagus, Xylomyia, and one or two other genera were for 

 many years regarded as a separate family, but the resemblance 

 between them is more apparent than real ; and^ Osten-Sacken, 

 who very closely criticised Brauer's paper on the characters of the 

 NOTACANTHA (Berl. ent. Zeit. xxvi, p. 363), showed satisfactorily 

 that they (Xylophagus and Xylomyia) cannot both come in the 

 same ultimate subdivision. 



Genus RHACHICERUS, Walk. 



Rhachicerm, Walker, List Dipt. Brit. Mus. v, Supp. i, p. 103 (1854). 

 ? Rhyphomorpha, Walker, Proc. Linn. Soc. Lond. v, p. 275 (1861). 

 Antidoxion, Snellen v. Vollenhoven, Versl. Meded. Kongl. Akad. 

 van Wetensch. Afd. Natuurk. xv, p. 1 (1863). 



GENOTYPE, Ehachicerus fulvicollis, Walk.; the original species. 

 " Body slender, nearly linear, cylindrical. Head transverse, 

 nearly as broad as thorax, vertex narrow. Eyes large, with small 



