% 

 NO. 2192. DRAGONFLIES, CALIFORNIA AND NEVADA— KENNEDY. 611 

 20, LEUCORRHINIA GLACIAUS Hagen (?). 



A Leucorrhinia was seen. Probably this. 



The following series of lists are concerned with the drainage east 

 of the crest of the Sierras. Two stream systems are included. 

 Truckee River rises in Lakes Tahoe, elevation 6,000 feet, and Donner, 

 elevation 5,000 feet. It flows down the abrupt east slope of the 

 Sierras and empties into the salt Pyramid and Winnemucca Lakes in 

 the Nevada desert. The other system concerned is that of the 

 Humboldt River, which rises in the mountains in eastern Nevada 

 and, flowing west, empties into the great shallow alkaline lake called 

 Humboldt vSink. These are two fragments of the old Lake 

 Lehontin System. 



DONNER LAKE, NEVADA COUNTY, CALIFORNIA. 



From July 23 to 26 I collected about Truckee and Donner 

 Lake, which lies 3 miles west. Tliis clear blue lake, 3 miles long 

 and a half mile wide, when it mirrors in its glassy surface the green, 

 pine-clad mountains which rise almost from its pebble beach, is one 

 of the most beautiful of the Sierra lakes. The east shore is a gravel 

 beach. This changes gradually into the cobble beach along its 

 north shore, which again at its west end merges into a short pure 

 sand beach. At its eastern end the lake drains by Donner Creek, 

 which meanders through a series of green meadows into Truckee 

 River. In this narrow vaUey, just east of the confluence of Donner 

 Creek with Truckee River, lies the town of Truckee. In the spring- 

 fed boggy meadow near the town slaughterhouse were collected 

 various species mentioned below. This high mountain region is 

 characterized by its Canadian dragonflies, but, oddly enough, it 

 has with this fauna a few species usually associated with lower, 

 warmer altitudes. These are discussed as they occur in the list. 



1. LESTES CONGENER Hagen. 



Common everywhere there is standing water, but not found in 

 Donner Lake. 



2. LESTES DISJUNCTUS Selys, 



Several were taken in a bog pool near the outlet of the lake. 



3. LESTES UNCATUS Kirby. 



Common in all swampy places. 



4. ARGIA EMMA Kennedy. 



Several were taken in the outlet. Probably because of the size 

 and depth of Donner Lake its waters keep the creek rumiing during 

 the winter. This and the next species were surprises from a warmer 

 fauna. 



5. ARGU VIVroA 



Abundant about the lake shore, where it breeds in the numerous 

 spring streams crossing the beaches. 



