NO. 2192, DBAGONFLIES, CALIFORNIA AND NEVADA— KENNEDY. 587 



of the Coast Mountains, while palmata lives mostly on the colder 

 streams of the Sierras. The ranges of the two species touch around 

 San Francisco Bay. I have two female palmata from Stockton. A 

 single female, wliich is probably palmata, was collected on Stevens 

 Creek, Santa Clara County, California, wliich is only a few miles from 

 Stanford. On tliis same creek I collected several exuviae of waTkeri. 

 These records from the neighborhood of Stanford are the northern- 

 most records for walkeri and the farthest southwest records for 

 palmata. 



Since writing my first description of this species (not published) I 

 found it very abundant on Santa Cruz Island, August, 1915. This 

 mountainous island, 23 miles oft' the coast of California, contained 

 no water except that found in the small, clear spring streams flowing 

 down the narrow mountain gorges wliich opened to the sea at various 

 points in the line of chffs wliich surround it. 



Aeslma walkeri was most abundant on the stream flowing down at 

 Fry's Harbor. This stream was about 2 miles long and in that length 

 fell over a thousand feet. It flowed down from Mount Diablo, a rocky 

 crag rising to a height of about 3,000 feet. The canyon containing 

 the stream was a V-shaped gorge a thousand feet deep with its sides 

 covered with a thin growth of grass and scattering clumps of live 

 oaks, where they were not too precipitous for vegetation. 



Except in one or two places, either one or both banks of the stream 

 were nearly vertical walls of rock and the course was broken every 

 few hundred feet by a waterfall of from 10 to 40 feet. In places the 

 stream was shaded by Uve oaks and alders, and here and there great 

 clumps of green sword ferns, 7 feet high, gave a pleasing rehef to 

 the gray and brown of the naked rock. In several quarter-mile 

 stretches the course of the stream was so deep that its bed was a fairly 

 smooth trough of rock, being too steep to retain the rocks and sand 

 washed down from above. Such stretches frequently contained 

 pools, mere rock bowls, 6 to 10 feet in diameter, fllled with water, in 

 which green clouds of filamentous algae floated over the black leaves 

 and vegetable trash in the bottom. Such pools were ahve with tad- 

 poles, Aeslma walkeri nymphs, and ArcJiilestes nymphs. The upper 

 half-mile of the stream was very stagnant, and here Argia vivida 

 flourished. At no place in the stream did aquatic vegetation occur 

 and in only a few places did roots hang in the water. Because of 

 this lack of vegetation in which Aeslma usually oviposits, the habits 

 of this species were unusual. 



During the sunny part of the day the males are found coursing up 

 and down the creek. As there is usually a morning fog on the island, 

 which does not clear away until 9 o'clock, it is frequently 11 o'clock 

 before the Aeslma males are on the creek. They then persist in flying 

 up and down uirtil the middle of the afternoon, when they leave the 



