AET.9 AMERICAN XYLOTINE SYRPHTD-FOES SHANNON 23 



trochanters unspurred; hind femur, both sexes, enlarged, without 

 protuberances, irregularly spinose beneath; frontal triangle of male 

 densely silvery pollinose; front of female broad; abdomen with 

 more or less well developed opaque markings. 



The genus Xylotodes is hardly separable from Xylotomima. The 

 shape of the head offers a better means of separating them than the 

 pilosity; also the width of the lower face (jowl) between the lower 

 margin of the eye and the side oral margin is broader in Xylotodes 

 than in Xylototnivia. 



KEY TO SPECIES OF XYLOTODES 



{Brachypalpufi, iu part) 



A\ Pile very short and inconspicuous ; wings witliout definite clouding. 



brevipilosus, new species. 

 A'. Pile fairly long and conspicuous ; wings with discal croi^svein clouded. 

 B\ Fourth tergite entirely blackish. 



C Third tergite shining bluish black plgra (Lovett). 



C". Third tergite bluish black on anterior half, subopaque posteriorly. 

 D\ Third antennal joint distinctly broader than long; ocellar pile 



and tarsi black metallifera (Bigot). 



D^ Third antennal joint about as long as broad. 



E\ Ocellar pile grayish ; tarsi brownish ; arista yellowish ; 



wings clouded on crossveins parvus (Willistou). 



E". Ocellar pile and legs black ; arista black ; all wing veins 



clouded sacawajeae, new species. 



B^ Fourth tergite with bright yellowish hind margin. 



inarmatxis ( Hunter ) . 

 Inarmatus apicaiicUis (CuiTan). 



XYLOTODES BREVIPJLOSUS, new species 



Female. — Medium size, dark species with very short pile. Head 

 triangular; front rather broad; ocelli placed well backward; front 

 dark brassy, a pollinose band across middle; first two antennal joints 

 longer than third, black; third joint broader than long, brownish; 

 arista 1.5 times length of antenna but much shorter than width of 

 face, dark brown; face covered with grayish pollen; face between 

 oral margin and eye much broader than width of third antennal 

 joint; mesonotum dark aeneous, pollinose anteriorly with semblance 

 of two median stripes which quickly fade into very dark non-poUi- 

 nose stripes; pile very short; legs black with bases of all tibiae yel- 

 lowish, anterior tarsi somewhat brownish ; metasternum pilose ; hind 

 femur moderately swollen, spinose posteriorly on lower side; abdo- 

 men dark aeneous, subopaque medianly and posteriorly on second and 

 third tergites ; wings diffusely clouded ; squamae white ; plumula and 

 halteres pale yellow. Length 9.5 mm., wing 7.5 mm. 



Ty2?e locality. — Blue Mountains, Washington, June, 1924 (V. 

 Argo). 



Type.— Cat No. 27742, U.S.N.M. 



