XYLOMYIA. 97 



two joints short, subequal, 3rd with eight ambulations and usually 

 a very small apical bristle. Thorax oval and subquadrate, slightly 

 arched ; scutellum unspined. Abdomen longer than thorax and 

 about as wide, 7-segmented ; genitalia distiuct. Legs rather long, 

 simple, except for the slight incrassation of the femora, especially 

 the hind pair, which are considerably thickened in some species 

 and often with a row of small spines on underside ; posterior tibiae 

 with two spurs. Wings longer than abdomen, not of the normal 

 Stratiomyid type ; veins not crowded together anteriorly, all 

 distinct aud attaining wing-margin ; costal vein reaching wing- 

 tip ; ambient vein present for some distance ; 2nd vein beginning 

 distinctly before base of discal cell, 3rd vein, originating shortly 

 after, the fork elongate, the lower branch ending at wing-tip ; 

 discal cell much more elongate than in any other subfamily ; 4th 

 vein with three terminations, the lowest one closing the 4th pos- 

 terior cell at wing-border ; posterior cross-vein very short or 

 absent ; anal cell closed distinctly but not considerably before 

 wing-border ; alar squamse small, thoracic pair absent. 



Fig. 8. — Xylomyia, wing. 



Range. Europe, the Orient, North, Central, and South America, 

 Canary Isles, and Natal. 



Life-history. Larva amphipneustic (though Luudbeck doubts if 

 it is truly so), broad, brown, leathery, with parallel sides, upper 

 and lower surfaces with bristles placed transversely on segments, 

 12-segmented, including head, which is broadly conical; mouth- 

 parts normally Stratiomyid ; last body-segment semicircular ; 

 oritice of respiratory chamber forming posterior extremity of body. 

 It lives in old trees or decaying wood. 



Xylomyia is a genus of yellow and black, rather Ichneumon-like 

 flies, with considerable outward resemblance to Xylophagus 

 (LEPTiDiE), but the closed 4th posterior cell will easily distinguish 

 them. The species seem to be much rarer in the adult than in 

 the larval stage. Solva, Walker, antedates Xylomyia by one year, 

 but as the subfamily name is constructed from the latter it should 

 be retained. 



Table of Species. 



Legs practically wholly yellow ; length, 4 mm. . . flavipes, Hoi. 

 Legs with distinct dark bands or markings ; leugth, 

 9-11 mm. 

 Hind tibia? yellow, tips broadly black ; length, 



9 mm calopodata, Big. 



Hind tibia? black, upperside pale at base ; length, 



11 mm , nigricornis, sp. nov 



H 



