118 MISSOURI BOTANICAL GARDEN. 



question which arises is that concerning the relationship be- 

 tween the number of flowers formed and the number of 

 fruits maturing per inflorescence. Unfortunately it is not 

 possible to determine with absolute certainty the number of 

 flowers formed from an examination of the mature fruit 

 clusters. But from the scars left by the falling of the flow- 

 ers failing to develop mature fruits it is possible to obtain a 

 pretty close approximation, and I venture to publish the 

 data after warning the reader that the frequencies are per- 

 haps not absolutely trustworthy, though the best we could 

 determine under the circumstances. 



Table I shows the correlation between the number of 

 flowers formed and the number of fruits maturing on the 

 384 inflorescences of our sample. The constants which are 

 of service are : 



Mean number of flowers 11.948±.110 



Standard deviation of flowers 3.202 ±.078 



Coefficient of variation of flowers 26.80 



Mean number of fruits 6. 578 ± . 1 10 



Standard deviation of fruits 3. 196 ± .078 



Coefficient of variation of fruits 48. 58 



The coefficient of correlation between the number of flowers 

 formed and the number of fruits developing is 



r = .572±.023. 



The degree of interdependence between these two char- 

 acters is therefore very considerable. But isolated con- 

 stants of this kind are of httle interest; to give them the 

 greatest significance a sufficient number of such correlations 

 should be worked out to make the problem a comparative 

 one. It will be of considerable physiological interest, I im- 

 agine, to determine how closely the number of fruits develop- 

 ing per inflorescence in distinct species, or in series of the 

 same species taken in different habitats, is dependent upon 

 the number of flowers formed. The only case available for 

 comparison is that of the immature inflorescence of Staphy- 

 lea * where we find a correlation of about 0.46. With a be- 

 ginning once made, data of this kind will gradually accumu- 

 late. 



* Harris, J. A. Biometrika. 6 : 441. 1909. 



