NO. 1710. NORTH AMERICAN DRAOONFLIES— WILLIAMSON. 383 



Material examined. — Wister, Oklahoma, Poteau River, August 3, 

 5, and 6, 7 males, 2 females, Frank Collins. Dallas, Texas, male and 

 female. Ball (M. C. Z.). Total, 8 males, 3 females. 



Under this name I have included 3 males, which future material 

 and study may reveal are specifically distinct. 



Ijength of abdomen, 50.5-54 mm. Length of front wing, 46.5-48 

 mm. Length of hind wing, 44-47 mm. Length of first tibia, 7-7.5 

 mm. ; hind femur, 11-12 mm. Length of tibial keel in length of tibia: 

 First tibia, ^ — to h; middle tibia, |. 



The yellow ring on 8 is narrowed laterally, widened dorsally and 

 ventrally, and encircles the segment; in all the other material of 

 australensis the dorsal and ventral yellow areas on 8 are separated by 

 black, excepting in one individual where the abdominal spots are 

 very large with the yellow spot on 6 not divided in the median dorsal 

 line by black; in the 3 males under discussion the spots on 6 vary 

 from 0.5-1 mm. in diameter and are distinctly to widely separated in 

 the middorsal line. The stigma is yellow-brown to black. 



Material examined. — Hyattsville, Maryland, July 4, 1899, male, J. S. 

 Hine. Gynn's Button Mill, Maryland, September 20, male (M. C. Z.). 

 Blount Springs, Alabama, July 18, 1890, male, Charles C. Deam. 

 Total, 3 males. 



MACROMIA GEORGINA de Selys. 



Length of abdomen: Male, 50.5-54 mm.; average, 51.8; female, 54 

 mm. Length of front wing: Male, 47.5-50 mm.; average, 48.8; fe- 

 male, 53 mm. Length of hind wing: Male, 46-48 mm.; Average, 

 47; female, 51 mm. Length of first tibia, male, 8 mm.; hind femur, 

 male, 12 mm. Length of keel in length of tibia, male: First tibia, |; 

 middle tibia, j to f . 



Humeral stripe present, about 3 mm. long on the mesepisternum; 

 otherwise similar to australensis. 



Male. — Very close to australensis; the abdominal spots on 3-6 

 decreasing in size very slightly posteriorly ; spots on 7 and 8 encircling 

 the segments. Abdominal appendages similar to australensis and 

 illinoiensis, but the superiors have a small, distinct, basal, dorsal yel- 

 low area, and the inferior appendage is distinctly paler than the 

 superior appendages. 



Female. — Separated from australensis by the longer antehumeral 

 thoracic stripe and the larger abdominal spots, especially on 3-5 

 (1-2 mm. long in australensis; 1.5-2.5 in georgina). The vulvar 

 lamina is a very short plate with converging sides, broadly and shal- 

 lowly emarginate. 



This is the only species in the material before me to which, I be- 

 lieve, EpophtJialmia georgina de Selys can be referred. In the female 

 the stigma is yellow-browTi, the costa obscure yellowish brown (in 

 the male the costa has the basal median area yellow, but this yellow 

 disappears with the narrowing of the costa which beyond this point 



