1889.] A. UvLkho-p&dhjaj—ElUj>tic Functions and Mean Values. 231 



whidi gives 



(o + J) (aB + i2) 



Wdr 



(28) 



If we compare the right hand side of this equatioa with the right hand 

 side of (13), we find that, if in (13) we interchange a and c, we obtain 

 exactly the same expression as in (28) ; similarly, the values of A' and 

 B' in (26) and (27) are derivable from the values of A and B in (10) 

 and (11) by interchanging a and c in the latter ; hence, the value of the 

 right hand side in (28) is obtained from the value of the right hand 

 side of (13) by interchanging a and o in the latter. 



30 



