THE CANADIAN ENTOMOLOGIST 231 



Genital lobes small. Appendages 2-23^ times as long as segment 

 10. See PI. XIII, figs. 10, 11. Viewed from above, cylindrical, 

 arching slightly entad, the flat tips, which are half the length of 

 the cylindrical bases, bent sharply entad at almost 90 degrees, then 

 curving caudad with their apices bent dorsad and cephalad. 

 Viewed laterally the externo-inferior surface of the appendage is 

 a longitudinal groove whose external edge has a blunt tooth at its 

 extreme base and the inferior or ental edge has a similar basal 

 tooth, htU this just caudad of the tooth on the external edge of the 

 groove. Viewed laterally the apical third or tiie flat tip bends 

 abruptly ventrad, then curves caudad, dorsad and finally cephalad. 

 Inferior appendage about half the length of the superiors. Viewed 

 ventrally it is' triangular with its base more than half as wide as 

 the appendage is long. 



Female. — Colour as in the male but the prothorax with the 

 posterior lobe yellow. Anterior coxa yellow on the outer or pos- 

 terior side. Femora of anterior and middle legs brown on their 

 basal two-thirds. Front wings with a tinge of dusky in the sub- 

 costal space to the first cross-vein. Hind wings tinged along the 

 costal edge to beyond the arculus, also the first three basal cells 

 posterior to the median dusky. Pterostigmata brown. 



Abdomen with a pale area on the side of segment 1 and three 

 pale areas on the side of segment 2, the dorsal one of the three 

 being circular and twice the diameter of either lower spot. A 

 large, circular, basal spot on the side of segment 3. (Segments 

 4 and 5 missing.) Obscure, minute, lateral spots on segments 6 

 and 7. Articulatory membrane between segments 2 and 3 white, 

 between segments 7-8, 8-9 and 9-10 pale. 



Vulvar lamina scoop-shaped, reaching to the middle of seg- 

 ment 10. It is more heavily chitinized than in the type female of 

 hudsonica. The sternum of segment 9 reaches barely to the middle 

 of segment 10. Appendages lacking. 



This species has been confused with hudsonica. Figs. 5-8 

 are from the types of hudsonica in the Mus. of Comp. Zoo). Dr. 

 Walker has this true hudsonica, collected by Mr. Whitehouse at 

 Red Deer, Alberta.* 



*F. C. Whitehouse, Odonata of the Red Deer District. Can. Ent.. XLIX, 

 p. 100, Mar., 1917. 



