NO. 1710. NORTH AMERICAN DRAGONFLIES— WILLIAMSON. 397 



SUPPLEMENTARY NOTES. 



Since the foregoing manuscript was prepared more collecting has 

 been done at Bluffton, Indiana, and the following material has been 

 taken along the Wabash River: 

 Macro miatseniolata. August 1, 1909, 1 male. 

 Macromia wahashensis. July 25, August 1 and 5, 1909, 10 males, 1 



female. 

 Macromia illinoiensis. July 30, 1909, 1 male. 

 Macromia pacijica. July 25 and 30, August 1, 5, and 8, 1909. 18 



males, 1 female. 



The association of the four above-named species along the Wabash 

 River at Bluff ton during 1909 is thus established. 

 Macrornia wahashensis. Female. 



Length of abdomen, 58 mm.; hind wing, 52 mm. 



Lateral and dorsal spots on frons distinct, all about equal, rounded, 

 1 mm. in diameter. Dorsal thoracic stripes extending about two- 

 thirds across the mesepisternum. Latero-ventral metathoracic carina 

 with a narrow, interrupted, and obscured yellow line. 



Yellow ring on abdominal segment 2 narrowly interrupted dorsally, 

 the interruption widest anteriorly. Dorsal spots present on 3-8, 

 each spot divided longitudinally in the median line to form 2 spots, 

 excepting on segment 7. As compared with the female of txniolata 

 the following differences may be noted: In segment 3, in wahashensis, 

 the spots extend anteriorly from the transverse carina more than one- 

 half the distance to the base of the segment ; in tseniolata scarcely 

 more than one-third. In segment 4, in wahashensis, the spots are 

 about 4 mm. long and extend to within 1 mm. of base of segment; 

 in tseniolata the spots are about one-half as long, and extend scarcely 

 one-half the distance from transverse carina to base of segment. 

 Segments 5 and G in wahashensis have spots relatively as large as on 

 segment 4; tseniolata, in the same way, has the spots on these seg- 

 ments relatively the same size as on segment 4 of tseniolafei. Seg- 

 ment 7 in wahashensis not divided medianly, produced posteriorly 

 beyond the transverse carina as a small triangle on either side of 

 the median line; in tseniolata the spot is divided longitudinally in 

 the median line and is not produced posteriorly beyond the trans- 

 verse carina. On 8 in wahashensis there is a distinct subbasal spot, 

 divided in the middorsal line, consisting on either side of 2 smaller 

 spots, each about 1 mm. in its greatest diameter; the anterior and 

 lateral one of these is the homologue of the spots on the other seg- 

 ments, the posterior and more dorsal one is the homologue of the 

 projection posteriorly beyond the transverse carina of the spot 

 on 7; in fully adult tseniolata there seems to be no trace of this spot 

 on 8. 



