LIBRARY 



TRANSACTIONS AND PROCEEDINGS NEW YORK 



OF THE BOTANICAL 



Botanical Society of Pennsylvania""'^''''^' 



VOL. I, NO. 3. 

 PRINTED ON THE MRS. JAMES McMANES FUND. 



A Comparative Study of the Cytology and 

 Movements of the Cyanophyceas. 



iWITH PI,ATES XXIII-XXV.) 



Thesis presented to the Department of Philosophy, University of Pennsylvania. 



May 1903, in partial fulfilment of requirements for 



the Degree of Doctor of Philosophy. 



Read before the Botanical Society of Pennsylvania. October iSth, igoa. and 

 May 15th. 1903.* 



By Orville P. Phillips. M. S , Ph. D. 



The problem of heredity has been attacked from many 

 sides. Various theories concerning the transmission of char- 

 acteristics, whether acquired or otherwise, have been given 

 to the world, and as many have been withdrawn or proven 

 untenable, at least by some authorities. From Thales to 



* In view of the recent appearance of three valuable contributions 

 to the above subject, it may be stated that Dr. Phillips' completed 

 thesis was placed in my hands on May 3d, 1903, and has been in my 

 care since. Its publication has been unavoidably delayed till now, 

 but no alterations have been made on it. While the views here set 

 forth can claim no priority over those already published, their appear- 

 ance may aid in the settlement of disputed points. — ^J. M. Mac- 

 rAiu.ANE, Editor. 



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