344 ENTOMOLOGICAL NEWS [Oct., '13 



way. Later, however, it was found to be still alive and had 

 to be "rekilled" in the cyanide and repinned one or two times. 

 On March ist, it was found necessary to place it in the 

 cyanide bottle a fourth time, but even after fifteen hours 

 exposure, life was still evident (at this time the bottle readily 

 killed a cerambycid and Benacus"). By noon, March 2, it 

 was apparently dead and was repinned and placed in the 

 cabinet. For several days it exhibited no signs of life ; but 

 on March 7, it was livelier than ever. On March 8 it was 

 exposed to the cyanide for thirty-one hours and died apparent- 

 ly, since no other note concerning it was made. This is an 

 illustration of marked advantage in resistance of one species 

 over many others when exposed to adverse (but unnatural) 

 conditions. 



The Butterflies of Omaha, Nebraska (Lepid.). 



By R. A. LEUSSLER, Omaha, Neb. 



Omaha, Nebraska, is situated on the eastern margin of the 

 State, on the bank of the Missouri River, in latitude 41 deg. 

 16 min. Being geographically near the center of the United 

 States, this locality presents perhaps a rather varied butterfly 

 fauna. The surface of the country bordering the river orig- 

 inally consisted of heavily wooded bluffs cut into by deep 

 ravines at many places, with some low-lying, timber-covered 

 bottom land between the bluffs and the river. The original 

 surface has, of course, been greatly altered in the city itself, 

 but in the suburbs to the north and south much of the wooded 

 bluffs remain. This woodland strip extends westward from 

 the river for a distance of perhaps three miles, where it shades 

 off into rolling prairie. The bottom land has mostly been clear- 

 ed and turned into meadow. The principal native trees are 

 oak, ash, walnut, elm, ironwood, hackberry, basswood, redhaw, 

 willow, boxelder and cottonwood, while some of the native 

 shrubs to be found are hazelnut, gooseberry, currant, wild 

 plum, choke cherry, prickly ash, sumac, burning bush, bitter- 

 sweet, elderberry and wolfberry. Wild grape and poison ivy 



