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UNIVERSITY OF PENNSYLVANIA 
CHROMOSOME NUMBER AND PAIRS 
IN THE SOMATIC MITOSES OF 
AMBYSTOMA TIGRINUM 
BY 
ip* i 
CHARLES L. PARMENTER 
A THESIS 
PRESENTED TO THE FACULTY OF THE GRADUATE SCHOOL IN 
PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR 
THE DEGREE OF DOCTOR OF PHILOSOPHY 
Reprinted from the 
Journal of Morphology, Volume 33, Number 1, December, 1919 
Philadelphia 
tt> c t3 
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