236 Wisconsin Academy of Sciences, Arts, and Letters. 
4. Smaller species, 6.5 to 8.5 mm. long, with slender, narrow ab¬ 
domen, sides of mouth-edge black; bands on abdomen of 
female all interrupted; on the male the third is entire.... 
. fragila 
Larger species, 9 to 11 mm. long, abdomen more oval, cheeks 
and mouth-edge yellow . 
5. Abdominal bands broadly interrupted.. .divisa 
Bands entire or only slightly interrupted. felix 
6. Yellow band on third segment of abdomen goes over side mar¬ 
gins in nearly its full width.. 
Yellow band on third segment usually separated from the lat¬ 
eral margins, or at least greatly attenuated; bands either 
entire or interrupted .. emarginata 
7. Small, narrow species, 7 mm. long, with abdominal bands of 
female interrupted; male unknown . tenuis 
Larger, 10 to 11 mm. long, abdomen oval with bands on third 
and fourth segments entire or only sub-interrupted, male 
unknown . aenea 
63. X. aenea Jones. Figure 46. Two females from Dane County, 
August and September, I place here although they differ 
somewhat, as the following notes will show: 
Black stripe of front extends up to the antennae and 
expands. Third joint of antennae almost quadrate in out¬ 
line, rather large and opaque black, there being no indica¬ 
tion of yellow on the lower side. Lateral thoracic stripes 
rather distinct. Scutellum black at extreme basal corners. 
Band on fourth segment of abdomen slightly interrupted. 
Hind legs mostly black, yellow at base of femora and at 
knees. Wings slightly smoky. 
64. X. aequalis Loew. One female, July 6, 1905, Door County. 
65. X. divisa Will. Milwaukee, Bacine, and Burnett Counties. 
Also one female taken in Dane County, September 19, 
1918. 
66. X. felix 0. S. One female from Vilas County, August, 1913. 
67. X. emarginata Say. Milwaukee, Douglas, Burnett, Polk, 
Dane, and Dunn Counties. June to September. Figure 
47. I have one male specimen in which the frontal tri¬ 
angle is entirely yellow, with scarcely any indication of 
black; the antennae are also reddish. 
68. X. flavipes Loew. Numerous specimens from Dane and Mil¬ 
waukee Counties. May to August. 
69. X. tennis Osburn. One female from Milwaukee County, July 
4,1907. 
