NO. 2192. DRAGONFLIES, CALIFORNIA AND NEVADA— KENNEDY. 543 



This species resembles hison in appearance but is less intensely col- 

 ored and does not have the black pruinose infraepisterna, which dis- 

 tinguish hison from the other western species. 



Abdomen, male, 35-38 mm. ; female, 35-36; hind wing, male, 30-31 

 mm.; female, 33. 



I foimd this species emerging in abundance from the Columbia 

 River at Umatilla, Oregon, on July 10, 1913. I have one specimen 

 from the Columbia at Sherman, Oregon, and two from Satus Creek, 

 Yakima Comitj", Washington. The specimens collected in the Sac- 

 ramento basin show a lighter coloration than those from the Columbia 

 Valley, and I have described them separately. One specimen of this 

 dark form from Seattle, Washington, is in Calvert's collection in the 

 museum of the Academy of Natural Sciences of Philadelphia. 



The type of pJialeratus Needham which I have examined appears to 

 be this true occideniis. PJialeratus was taken on the Willamette 

 River (a tributary of the Columbia) at Corvallis, Oregon. Figure 211 

 is of the appendages of a male from Corvalhs. 



OPHIOGOMPHUS OCCIDENTIS CALIFORMCUS, new variety. 



Type. — Cat. No. 21144, U.S.N.M. A male, American River, Sacra- 

 mento, California, July 15, 1914. 



Allotype. — Cat. No. 21144,U.S.N. M. A female, American River, 

 Auburn, California, July, 19, 1914. 



Colors, male. — Yellow with brown markings. (See fig. 212.) 



Face pale yellow, the frons narrowly edged beliind with black; 

 vertex black but with a large postocellar area yellow; occiput yellow; 

 eyes gray, darker above. 



Thorax yellow with a greenish cast. Markings as in occideniis, 

 but pale brown and much reduced in extent. A narrow brown mid- 

 dorsal stripe but antealar ridges yellow. Humeral stripe double, but 

 both lines narrow and separated b}^ a distance equal to one of them. 

 Second lateral suture with a mere suggestion of brown. Famt mark- 

 ings along the lower side of the thorax. Legs creamy white ; femora 

 tipped with black; tibiae black with an external pale stripe; tarsi 

 black. Costa yellow, pterostigmas dark brown; venation brownish 

 but the %vings otherwise hyaline. 



Abdomen yellow with brown markings except below the markings 

 on segments 3-6, which area is white. The sawtoothed lateral stripe 

 is reduced to a series of spots and is not broadly connected with its 

 fellow across the posterior ends of the segments 3-6, as in occidentis. 

 Segment 10 wholly yellow and only a trace of brown on segment 9. 



Female. — Color as in male but segments 1 and 2 almost wholly 

 yellow, and on segments 3-8 the lateral stripe more nearly continuous 

 than in the male. Segment 9 yellow except a black speck on apical 

 end of the middorsal Hne. Segment 10 and appendages yeUow. 



