THE 



KANSAS UNIVERSITY 

 SCIENCE BULLETIN. 



Vol. XIII, No. 5— May, 1920. 



CONTENTS : 



A Calculation of the Invariants and Covariants for Ruled 



Surfaces, 



E. B. Stouffer. 



PUBLISHED BY THE UNIVERSITY, 

 LAWRENCE, KAN. 



Entered at the post-office in Lawrence as second-class matter. 



9-860 



