SCIENTIFIC PROCEEDINGS (109). 



The moments 2(x), S(* 2 ), S(y), S(;y 2 ),---, and the product 

 moments S(m), S(wy), , 2(yz) are available for the correlations 

 between size, which are required on their own account (Problem i). 



The constants for growth increments are given by well-known 

 formulae 



i pq = x-w, etc., 



and similarly for o^ r , o-,;, 



The product moment for any two growth increments, say 

 i pq and i rs , is 



In the special case in which three consecutive stages, say w, x, y, 

 are involved we write 



Problem j. To determine the correlation between the size 

 of the organism at any stage and any growth increment. 



The notation of problem (2) may be used. The physical 

 constants for the growth stages and growth increments have 

 been given. The product moments are 



- SO 2 ), 

 2(wy), etc. 



Illustrations of applicability will be given elsewhere. 



