374 PROCEEDIXGf^ OF THE XATIONAL MUSEUM. vol.37. 



the middorsal line (never divided in male), and the basal spots on 8 

 are reduced to a trace or, more usually, are wanting altogether. 



Wings hyaline or tinged with yellowish, most strongly in a teneral 

 specimen; in one or two cases the faintest trace of basal brown areas 

 in the costal spaces; stigma 3^ellow-brown to black, depending on age. 

 The examination of the wings of 7 females shows the following: Tri- 

 angle of front wing, free 2, crossed 12; subtriangle of front wing and 

 triangle of hind wing, crossed 14. 



Vulvar lamina apparently a slight thickening of the median pos- 

 terior edge of the sternum, with a slight folding into a shallow trough. 

 Abdominal appendages as in illinoiensis. 



This species can be confused only with the next. Differences are 

 indicated in that description. It is the largest of our Macromias. 

 For living colors see note under next species. 



Material examined. — Rosslyn, Virginia, July 30, 1899, female, G. N. 

 Collins (U.S.N.M.). Washington, District of Columbia, July 10, 1902, 

 female, W. C. Weeden (U.S.N.M.). Toledo, Ohio, August 1, 1894, 

 male, J. S. Hine (O. S. U.). Napoleon, Ohio, July 9, 1898, female, 

 J. S. Hine. Elkhart, Indiana, May 31, 1896, teneral female, in thick 

 woods, R. J. Weith (P. P. C). Fort Wayne, Indiana, July 18, 1901, 

 5 males, E. B. WiUiamson (1 U.S.N.M.) ; August 3, 1902, female, E. B. 

 Williamson. Bluff ton, Indiana, August 6, 1905, male; August 8, 

 1905, male; August 11, 1907, male; August 1, 1908, 2 males, 1 fe- 

 male, E. B. Williamson. Without data, female (O. S. U.). Total, 

 11 males, 7 females. 



MACROMIA WABASHENSIS, new species. 



Length of abdomen: Male, 51-57 mm.; average, 54.4. Length of 

 front wing: Male, 47.5-50 mm.; average, 49. Length of hind wing: 

 Male, 46-48 mm.; average, 47.3. Length of first tibia, male, 8 mm.; 

 hind femur, male, 12.6 mm. Length of tibial keel in length of tibia, 

 male: First tibia, f ; middle tibia, J — to ^.^ 



Very similar to tseniolata, but may be recognized by the following 

 characters: Costa (and antenodals and postnodals) yellow or yellowish 

 as far as stigma or tip of wings; labrum less obscured, face paler and 

 brighter colored; lateral spots on frons distinct (indistinct in two 

 specimens) ; dorsal abdominal spot on 8 similar in shape and extent, 

 relative to the transverse carina, to the spot on 7 (in two specimens a 

 very narrow dorsal basal yellow ring on 9). (The spot on 8, relative to 

 the area of the segment, is really more extensive than on 7, since on 

 7 there is a wider basal ring of black, though, compared with each 

 other, the spot on 7 is larger than the spot on 8.) 



Wings tinged with pale yellowish or hyaline (in about equal 

 numbers), the extreme apex frequently slightly fumose; in 4 speci- 

 mens a trace of brown spots in basal costal space. (See fig. 4.) 



" In one specimen, which otherwise seems to belong here, the tibial keel of mid- 

 dle tibia is \. 



