574 Curves of Coinpositae and UmhclUfcrae. 



Increase 

 1892 1893 1894 1893—1894 



Aiiethum graveolens 18.3 21.2 25.2 +4.0 



Chrysanthemum segetum 13 — 14 13.1 13.1 0.0 



Coreopsis tincioria d=8 8.1 7.9 —0.2 



Bide7is gi^andiflora ± 5 5.2 4.9 —0.3 



Coriandrum sativum ±5 5.1 4.3 — 0.8 



Madia elegants ±21 18.9 17.9 -1.0 



The varying result of the conflict between heavy 

 manuring for three years and the selection of individuals 

 with a small number of rays is shown by the figures in 

 the last column. 



I shall now exhibit the values for Q/M in a single 

 table. Q, as we have already said, may be made inde- 

 pendent of the nature of the varying character by di- 

 viding it by M ; and in this way the amplitudes of varia- 

 tion of the different characters may be compared with 

 one another. The subjoined values for 0/M are the 

 means calculated from two or more generations in all 

 the above cases. I have added Oenothera Lamarckiana 

 to the list. 



M 



Anethwm graveole^is 0.16 



Coriandrum sativmn 0.11 



Oenothera Lamaixkiafia .... 0.08 



Bidejis grajidiflora 0.08 



Madia elegans 0.08 



Coreopsis tincioria 0.04 



Chrysanthemum segetum . . . . 0.03 



The observed amplitudes of variation, estimated by 

 this measure, differ considerably from one another. But 

 they are, of course, also affected by selection and nutri- 

 tion. 



The phenomena of fluctuating variability are, there- 



