518 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



there. This, then, would appear as a general migration of the 

 imagoes upstream. 



Figs. 133-137.— Coedulegasteb diadema. 133-134. Color pattern. 135. Segaient 10 of male. 



136. fobe leg of male. 137. segments 9 and 10 of female. 

 Figs. 138-143.— Cordulegaster dorsalis. 138-139. Color pattern. 140. Penis and hamules. 141. 



Segment 10 of male. 142. Segments 9 and 10 of female. 143. Eggs. 



I have never observed copulation in tliis species, but in the matter 

 of oviposition I was more fortunate. August 16, on Stevens Creek, 



