194 Nebraska State Horticultural Society. 



transportation of the seed by the wind either in the whole strobilus, or 

 the separate seed-bearing bags. The tree is abundant in the Missouri 

 forests, from which it has extended up through the eastern and northern 

 counties to Brown, Cherry and Sioux counties. 



Water Beech (Carpiiius caroliaiana Walter.). The small nut is 

 attached to a foliaceous, somewhat three-lobed bract, which serves as a 

 wing. These bracts are not crowded into a strobilus, but constitute a 

 loose raceme. On falling from the tree the bracts serve to float the 

 seed in the wind for some distance frOm the parent tree. This species 

 occurs in the Missouri forests, and has been reported from eastern 

 (Sarpy county) and northern stations (Brown county) in Nebraska to 

 which it has apparently extended its range. 



The Birches (Betula spp.). The little nut is winged on its mar- 

 gins. These grow in small cones, from which when mature they are 

 shaken out by the wind, and carried away some distance before reach- 

 ing the ground. 



Canoe Birch (Betula papyrifera Marshall). This tree occurs ia 

 Minnesota and Montana, the Black Hills of North Dakota, and at a 

 single station on the Iowa river in central Iowa (Hardin county). In 

 Nebraska it is found only on the bluffs and in the ravines along the 

 Niobrara river in Keya Paha, Brown and Cherry counties. The occur- 

 rence of this tree in Nebraska is a puzzle to the botanical geographers, 

 for it is difficult to conceive of any means by which the seeds could be 

 carried from the nearest known stations. Even should we consider the 

 possibility of its dissemination from the Black Hills the difficulty is 

 nearly as great, for the distance is fully 150 miles, a part of it across 

 the very rough country known as the "Bad Lands." 



Black Birch (Betula occidentalis Hook.) occurs abundantly in 

 the Rocky mountains west of Nebraska and has extended from thence 

 eastward into the state in Sioux county. 



River Birch (Betula nigra L.) is found in the Missouri forests 

 southeastward, and has extended its range northward along the eastern 

 border of the state, being reported from Cass county. 



HAIRS. 



The Willows (Salix spp.). The bicarpellary seed-pods contain 

 two rows of inverted seeds (anatropous), each of which develops a cir- 

 cular tuft of long straight ascending hairs on its funicle. Upon the 

 dehTscence of the mature fruit the seeds are released, when the hairs 



