191 j] Muttkowski, Studies in Tetragoneuria. 97 



Wings may be entirely hyaline without trace of spots, the mem- 

 brane sometimes with faint fumose. In every case the front wings 

 are without spots and the maximum development of color in the hind 

 wings is as follows : a basal spot on either side of the subcostal vein 

 most developed on the posterior side (in the subcostal space) and 

 extending along the vein to the first antenodal, the membrane on 

 either side of the first antenodal slightly but distinctly tinged with 

 brown in the subcostal space; a basal spot in the cubital space, 

 reaching about half way to the cubito-anal across vein, which may 

 have brown traces on either side and posterior to it ; a brown spot in 

 the anal triangle on either side of the cross vein, its greatest area on 

 the anterior side of the cross vein, in its maximum development the 

 anterior third and posterior third or fourth of the anal triangle 

 remaining hyaline ; the V-shaped cross vein on the distal side of the 

 anal triangle margined with brown. Costa front wings distinctly 

 yellow at base. Membranule white, in the male more or less with 

 brown posteriorly against the anal triangle. 



Legs dark reddish brown, bases of all and femora of the first 

 pair pale. 



Abdomen long and slender when compared with species of the 

 cynosura group. $. — Seen in profile of nearly uniform width after 

 segment 3. segments 2 and 3 moderately dilated and largely yellowish, 

 slightly darker than the thorax in color. From above the last seven 

 segments are of nearly the same width, black in color, each segment 

 with a long yellow spot on either side, reaching the lateral margin, 

 and on the anterior segments occupying the entire length of each 

 segment except the extreme apex and base, reduced on the posterior 

 segments and not present on 10 ; articulations between segments a 

 narrow yellow ring; the lateral spots on the last seven segments, 

 described above are so nearly joined that the abdomen might be 

 described as black with a yellow interrupted stripe on each side. The 

 black area on the dorsum of segments five and six at the narrowest 

 point is 1.5 to 2 mm. wide. 



5 . — Flattened in profile, in dorsal view tapering from 3 to the 

 apex ; in dried material distorted and shrunken as is so frequently 

 true of the females of many Cordulines. Similar in color to male, the 

 black dorsum beginning on 2, and the lateral spots continuous, form- 

 ing lateral yellow stripes, and extending on to 10. 



Male abdominal appendages. — Superior appendages seen in profile 

 spatulate, with an obtuse inferior angle at one third the length, this 

 angle inconspicuous ; if the appendages of Stella and any of the 



