NO. 2192. DRA00NFLIE8, CALIFORNIA AND NEVADA— KENNEDY. 555 



The specimens I took in Nevada I consider a distinct variety and 

 will discuss them separately.' 



At Sacramento several miles of the American and Sacramento 

 Rivers were explored, but this species was found only on the American 

 River and was confined to that stretch just below the Southern 

 Pacific bridge. 



The river at this point was about 200 feet wide with sand bottom 

 and sand shores except along the north shore at the deepest point, 

 where it was 6 feet in depth and the steeper bank showed some clay. 

 Later, in August, the water had fallen until it was only about 3 feet 

 deep at this point. The shore here was bordered with cottonwoods, 

 whose dark green tops rose above a Ime of paler willow bushes, which 

 hung in the muddy water, while the river bottoms adjoining were an 

 almost continuous thicket of box elder trees, about 30 feet high. In 

 one or two places these box elder thickets thinned out and such 

 glades were rank with grass and clumps of willows. 



The males of olivaceus were abundant over the yellow river, where 

 they flew leisurely in a broadly zigzag course at a distance of not more 

 than 10 inches above its surface. At intervals they rested, usually 

 in a hanging position, on the willows. The females were not much in 

 evidence. Two were observed over the water and were swifter and 

 more direct in their flight than the males. Several females were 

 taken in the open willow glades back from the river. Here they 

 rested on the bushes and weeds, sunning themselves. Here an occa- 

 sional male wandered about apparently seeking a mate. When found 

 the pair would fly away in a short nuptial flight, soon coming to rest 

 on bushes where they remained in copulation indefinitely. Individ- 

 uals were difficult to catch in these glades, because on being disturbed 

 they would fly up out of reach. The large series was taken by wading 

 breast deep in the river's edge and scooping them off of the willows. 

 Much time was spent searching for exuviae, but none were found. 



The illustrations (figs. 263-271) show the structural pecuHarities of 

 this species. The foUowing is a description of the live colors: 



Male. — Labrum pale grayish with greenish brown tmts. Frons 

 slightly browner than labrum, but paler except for a black band 

 across its posterior edge. Vertex black except posterior to the 

 ocelli, which with the occiput is pale grayish brown. Eyes blue, 

 paler below. Postocular area pale brownish gray, shading mto a 

 bluish gray above. (See fig. 250.) 



Prothorax dark brown except the anterior lobe which is yellow. 

 Mesothorax with a black middorsal stripe twice as wide below as at 

 the antealar sinus. Antealar sinus brown, connecting the middorsal 

 stripe with the very wide humeral suture. Usually included in this 

 stripe is a gray hair line lying posterior to the suture and a slightly 



1 See p. 557 of this paper. 



