238 Wisconsin Academy of Sciences, Arts, and Letters. 
2. Front of female only a little narrowed above; smaller species, 
5 or 6 mm. long, abdominal markings variable.. marginata 
Front of female considerably narrowed above; larger species, 8 
or 9 mm. long; abdominal markings more regular, rather 
“blocked out” . polita 
71. M. geminata Say. Numerous everywhere. Early spring to 
late fall. Figures 50, 51, 52. 
72. M. marginata Say. More common than geminata; throughout 
the season. Figures 53, 54, 55. 
73. M. polita Say. Milwaukee, Dane, Fond du Lac, and Winne¬ 
bago Counties. Midsummer to late fall. 
Sphaerophoria St. Fargeau and Serville 
(After C. W. Johnson) 
1. Lateral thoracic stripe distinctly ending at the suture. 2 
Lateral thoracic stripe continuous. 3 
2. Face entirely yellow, abdominal bands beyond the second seg¬ 
ment present in the female, usually obsolete or wanting 
in the male; length 8 mm. cylindrica 
Face with a wide black stripe, abdominal bands similar in 
both sexes; length 6 mm. novaeangliae 
3. Abdomen in the male with a series of yellow spots, in the fe¬ 
male with widely interrupted bands narrowly connected 
with the lateral margin; length 8 mm. (strigata) 
Abdomen with bands on the first four segments except the first, 
the others irregularly marked with black; length 8 to 
10 mm... scripta 
74. S. cylindrica Say. Cosmopolitan, May to October. Figure 
56. 
75. S. novaeangliae Johnson. One female, Vilas County, and one 
male, Dane County. 
76. S. scripta Linn. Cosmopolitan. May to October. Figure 
57. Often confused with cylindrica. 
Sphegina Meigen 
77. S. campanulata Kobertson. One female from Vilas County. 
78. S. lob at a Loew. Vilas County. 
