342 



— Hind coxae yellow; hind femora darkened on apical third; eyes 

 separated by more than one fifth the head-width; furcation of 

 fourth and fifth branches of radius distinctly proximad of, or in 

 line with, a line drawn from apex of that vein to point of furca- 

 tion of first and second branches of media tenfhredinoides. 



Xyi^omyia pai^upEs Loew 



Subtila pallipes Loew, Berl. Ent. Zeitschr., 1863, p. 6. 



I,ar7>a. — Length, 7-9 mm. Dark brown, head and thoracic seg- 

 ments yellowish, the latter darkened on sides and posteriorly. 



Protruded portion of head slightly longer than prothorax, the dor- 

 sal surface with several strong hairs (PI. XLVIII, Fig. 15), labrum 

 conically produced, the apex very sharp (PI. XLVIII, Fig. 4) ; man- 

 dibles recurved, slightly dentate; maxillae prominent, their ventral 

 surfaces with numerous narrow transverse ridges, palpi inconspicuous 

 (PI. XLIX, Fig. 7) ; labial plate as in Figure 10, Plate XLIX; an- 

 tennae sessile ; eyes distinct but not protruded ; ventral surface of head 

 wath a long hair on each side in transverse line with the eyes. Sur- 

 faces of thoracic and abdominal segments finely shagreened excepting 

 a large irregular area on dorsum of prothorax, a narrow transverse 

 area on ventral surface of same segment, a pair of narrow transverse 

 plates on dorsum of metathorax, and the tubercles on the various 

 segments. Prothoracic spiracle wdth 3 openings (PI. XLVIII, Fig. 

 9). Abdominal segments 2-7 each with a transverse series of small 

 round warts near anterior margin on dorsum ; eighth segment with 7 

 rather large w^irts in an irregular (2, 3, 2) transverse series proximad 

 of median line, posterior lateral angle with 2 small warts; all ventral 

 segments with a closely placed series of small warts on their anterior 

 margins; anal opening slightly T-shaped, the margins toothed; spi- 

 racles distinctly separated, situated within an apical chamber whose 

 margins protrude lip-like from apex of eleventh segment and appear 

 like an additional segment; thoracic and abdominal segments, except 

 the apical one, each with 6 hairs, one on each lateral margin and one 

 on each side on venter and dorsum; apical segment as in Figure 14, 

 Plate XLVIII. 



This description was drawn from larvae obtained by me October 

 21, 191 6, under the bark of trees which had been felled in the spring 

 of the same vear. The bark was beginning to loosen, and larvae of 

 Huxesta, Lonchaea, and Hetcromcringia were abundant under it. The 

 Xylomyia larvae were found to be predaceous, feeding indiscriminate- 

 ly upon the other larvae. They have a peculiar habit of raising up 

 the thoracic segments when disturbed, but are very sluggish. 



