THE UNIVERSITY OF CHICAGO 
AH ECOLOGICAL SURVEY OF THE PORCUPINE MOUNTAINS 
A DISSERTATION 
SUBMITTED TO THE FACULTY 
OF TEE OGDEN GRADUATE SCHOOL OF SCIEHCE 
IH CANDIDACY FOR THE DEGREE OF 
DOCTOR OF PHILOSOPHY 
DEPARTMENT OF BOTANY 
CHICAGO.ILLINOIS 
NOVEMBER. 1923 
ftp;.; * 
^ , A 
