ART. 11 CHRYSOTOXINE SYEPHID-FLIES SHANNON 7 



Type.— Msile, Cat. No. 28665, U.S.N.M. Allotype female; six 

 paratypes male and female. Other paratypes in V. Argo's collection. 



I)ist)-ihution.—-Wa.sh'm(^ton: Lewis Peak, Blue Mountains. July 

 (V. Argo); Mount Adams, 4,000-6,000 feet, July (M. C. Lane). 

 Locality? (Williston collection). Oregon: Mount Hood (Wiliiston 

 collection). Idaho: Mount Moscow, July (J. M. Aldrich; H. C. 

 Shannon) ; Bitter Root Mountains, July (C. V. Piper). 



CHRYSOTOXUM VENTRICOSUM Loew 



Chrysotoxum rentricosum Loew, Berlin Ent. Zeit., vol. 2. 1864, p. 44. — 

 Johnson, Psyche, vol. 14, 1907, p. 77; Occ. Papers Boston Soc. Nat. 

 Hist., vol. 5, 1924, p. 97. 



The species may be recognized by the rather globose and evenly 

 rounded abdomen, short antenna, the arista being much shorter and 

 the third joint but little longer than the combined length of the 

 basal ones; second sternite black except sometimes on anterior mar- 

 gin; the arcuate abdominal bands usually slender, narrowly inter- 

 rupted at the middle and separated from the margins of the tergites; 

 first tergite usually entirely black; frons of male usually black 

 pilose; pteropleura usually bl^ck, pilose; sternopleura usually with- 

 out yellow spot ; base of f elnora usually black ; size 7-13 mm. 



Small specimens are sometimes misidentified as derlvafum Walker. 

 Three specimens (Idaho, Oregon, New Mexico) have the second and 

 third arcuate bands entire. 



Type locality. — Washington State. 



Type. — In Cambridge Museum of Comparative Zoology. 



DistHhution. — Saskatchewan: Farewell Creek, July (V. A. Arm- 

 strong). British Columbia: South Fork, August 11, 1903 (E. P. 

 Currie). Idaho: Moores Lake, Jidy 10, 1907 (J. M. Aldrich); 

 Bitter Eoot Mountains, July (C. V. Piper). Washington: Bona- 

 parte Lake, 4,000 feet, July 4, 1921 (M. C. Lane) ; Lewis Park, 

 Blue Mountains, July 1, 1923 (V. Argo). Locality? (Willis- 

 ton collection). Oregon: Mount Hood (Wiliiston collection); 

 Mount Hood, August 18, 1923 (G. P. Engelhardt) ; Crater Lake, 

 7,000 feet, August (G. P. Engelhardt) ; Marys Peak, Corvallis, 

 July (G. P. Engelhardt) ; Manzanita, July 30, 1920 (L. P. Rock- 

 wood). Montana: Many Glaciers, July (G. P. Engelhardt). Colo- 

 rado: Locality and collector? Tennessee Pass, 10,240 feet, July 10 

 (J. M. Aldrich). New Mexico: Locality? (Wiliiston collection). 



CHRYSOTOXUM COLORADENSE Greene 



Chrysotoxum coloradensis Greene, Proc. Ent. Soc. Wash., vol. 20, 1920, 

 p. 70.— CuRRAN (in part), Can. Ent., vol. 56, 1924, p. 35. 



The entire arcuate bands on tergites 3 and 4 which attain the side 

 margins of tergites and absence of yellow spot on the sternopleura 



