374 NORTH AMERICAN FAUNA [No. 55 



General characters. Size and proportions about the same as in typical Myotis 

 evotis, but color lighter and brighter; upper parts a golden buff, lower parts 

 buffy or dull whitish ; ears and membranes black or dusky. 



Measurements. Adult male from Cedar Mountains: Total length, 85 mm; 

 tail, 44; foot, 10; ear (dry), 17; humerus, 36; spread of wings, 242. Adult 

 female from Sisters : 96 ; 45 ; 10 ; 18 ; 37. An Arizona specimen weighed 7.2 g. 



Distribution and habitat. Arid regions from eastern Oregon to 

 North Dakota and southern Mexico. Specimens are referred to this 

 form from Oregon collected at Disaster Peak, Cedar Mountains, Har- 

 ney, Burns, Twelve Mile Creek, Cornucopia, Wallowa Lake, Fossil, 

 Lehman, Deschutes River, and Sisters (fig. 93). Some of these speci- 

 mens, however, are more or less intermediate with the more western 

 and darker colored evotis. The records indicate that chrysonotus is 

 a common bat over the open country of eastern Oregon in Upper 

 Sonoran and Transition Zones, apparently spending the summer in 

 or near the edges of the Transition. 



On June 14, 1915, Preble shot one of these bats at about 7,000 feet 

 altitude on the slope of Disaster Peak, in the extreme southeastern 

 corner of the State, as it flew over the willow-fringed creek in the 

 evening. There were cottonwood trees 2 miles down the creek and 

 cliffs on the other side half a mile away, but no nearer refuge for a 

 bat. Later, on July 26, in the Cedar Mountains of eastern Oregon 

 he saw a bat flying slowly along the side of the mountain about the 

 middle of the forenoon. It alighted on some rocks close to the 

 water of a spring, evidently intending to drink, and was captured 

 and converted into a specimen. It was extremely lean, and its 

 flight suggested that it was weak from hunger, thirst, or disease, 

 which probably accounted for its appearance in daytime. 



In early July 1896, Preble and the writer each shot one at the 

 lower edge of yellow pines on Twelve Mile Creek, where they seemed 

 to be the commonest bat in the open sagebrush valley. Another 

 was collected on Squaw Creek, near the town of Sisters in open 

 yellow pine timber by L. J. Goldman on July 26, 1914, and another 

 28 miles northwest of Burns by M. E. Peck on August 9, 1912. 

 An old alcoholic specimen in the United States National Museum 

 collection from Camp Harney was undoubtedly taken by Bendire 

 in the seventies while he was stationed there, but is without other 

 data. An alcoholic specimen from Wallowa Lake, secured by W. C. 

 Kendall, September 24, 1897, gives the latest fall record for the 

 State and suggests the probability of a wintering cave at no great 

 distance. 



General habits. These are quick, strong flying bats and not col- 

 lected in great numbers even where common. In places they are 

 found around buildings and not infrequently come in through open 

 windows or doors in search of their food insects. They are some- 

 times found in caves and hollow trees, but not in large colonies. 



To what extent they are migratory is not known but this probably 

 depends on the location of wintering caves and summer breeding and 

 feeding grounds. Oregon is well supplied with extensive and little 

 known caverns, and undoubtedly with many available to bats and 

 not to larger animals. When the great value of bats to man is better 

 realized their winter retreats will be studied and carefully guarded. 



Food habits. Beyond the mere facts that they are seen zigzagging 

 against the sky, rapidly snapping up flying insects, and that their 



