THE PllAIRIE-GRASS FORMATION IN REGION I 



By John J. Thorwbeb 

 TNTKODUCTION 



During the last three years the writer has carried on several 

 lines of phytogeographical investigation about Nebraska 

 City, Neb., with a view of bringing results together ultimately 

 and presenting them to the Faculty of the University of Ne- 

 braska as a thesis for the degree of master of arts. On 

 account of school duties, the work has not been pursued as 

 vigorously at all times, particularly during late spring and 

 autumn, as was desirable. When circumstances were favor- 

 able, however, all possible aaste, consistent with a proper 

 degree of accuracy, was made. 



The pieces of apparatus needed were designed largely as 

 necessity dictated, and, as is generally the case under similar 

 circumst.ances, a desirable degree of accuracy was not always 

 obtained by their use. It is gratifying to know that now we 

 may expect greater precision in determining physical factors, 

 from the excellent and inexpensive apparatus designed by 

 Dr. Clements and Mr. Hedgcock of the University. 



To Dr. Clements in particular the writer is deeply indebted 

 for the invaluable assistance rendered from time to time, 

 for the many personal conferences, and for the timely sug- 

 gestions ever freely given. More than this, Dr. Clements has 

 furnished Many invaluable outlines for extended research, 

 and under his supervision alone what is now presented was 

 made possible. The "Phytogeography of Nebraska," by Drs. 

 Pound and Clements, was also a valuable incentive to the 

 work. To Mr. E. R. Yundt, of thei Nebraska City high school, 

 the writer is indebted for the accurate topwDgraphical survey 



