THE UNIVERSITY OF CHICAGO. 
FOUNDED BY JOHN D. ROCKEFELLER. 
Spermatogenesis of Normal and of 
Hybrid Pigeons. 
A DISSERTATION 
Submitted to the Faculties of the Graduate Schools of Arts» 
Literature^ and Science^ in Candidacy for the 
Degree of Doctor of Philosophy. 
DEPARTMENT OP ZOOLOGY. 
BY 
MICHAEL R GUYER. 
CHICAGO: 1900. 
