University Studies 



Vol. IV JULY, 1904 No. 3 



I. — Variation in the Hooks of the Dog-Tapezvorms, Taenia 

 serrata and Taenia serialis 



Part I 



BY EARLE C. STEVENSON 



This paper was submitted as a thesis for a master's degree in 

 the department of zoology at the University of Nebraska, Lin- 

 coln, (Studies from the Zoological Laboratory, under the Direc- 

 tion of Henry B. Ward, No. 59) in May, 1903. Since then Dr. 

 Carl C. Engberg, instructor in biometrics in the University of 

 Nebraska, has been able to work over the derived data and to 

 deduce from them more complete and extended conclusions than 

 would have been possible for one less versed in this field of 

 mathematics. I have accordingly deemed it for the best interests 

 of scientific investigation to withdraw entirely my somewhat in- 

 complete studies on the mathematical side of the question which 

 were contained in the original thesis, and to have the mathemat- 

 ical discussion appear as a whole in the second part of the paper, 

 for which Dr. Engberg accordingly becomes responsible. 



COLLECTION OF MATERIAL 



Under the direction and instruction of Dr. Henry B. Ward, I 

 took up the study of these parasites during the summer of 1901. 

 In cooperation with Mr. B. L. Doane, B. Sc, of the University 



University Studies, Vol. IV, No. 3, July, 1904. 



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