258 J. ARTHUR HARRIS AND H. S. REED. 



Thus plants which are growing more rapidly during one period 

 of development will grow more rapidly during a closely asso- 

 ciated period, but there is little or no relationship between the 

 growth increments of more widely separated periods. 



The growth increment of the organism is positively corre- 

 lated with its size at an immediately preceding stage. In the 

 early stages of growth, the growth increments of two or even 

 three subsequent periods are positively correlated with the initial 

 size of the organism. 



LITERATURE CITED. 

 Harris, J. Arthur. 



'20 Formula for the Calculation of the Correlations of Size and of Growth 

 Increments in the Developing Organism. Proc. Soc. Exp. Biol. and 

 Med. In press. 

 Pearl, R., and Surface, F. M. 



'15 Growth and Variation in Maize. Zeitschr. Indukt. Abst. u. Verer- 



bungslehre, 14 : 97-203. 

 Reed, H. S. 



'19 Growth and variability in Heliantluts. Amer. Jour. Bot., 252-271. 



'19 The Growth Rate of an Annual Plant, Heliantlnts. Proc. Nat. Acid. 



Sci., 5: 135-144. 

 Reed, H. S. 



'20 The Xature of the Growth Rate. Jour. Gen. Physiol., 2: 545-561. 

 Webber, H. J. 



'20 Selection of Stocks in Citrus propagation. Bull. Univ. Calif. Coll. Agr., 



