Trifoliiun lucaniatuiii Oiiadrifoliuiii. 239 



27% with a single abnormal leaf each, and 28% with two 

 to four 4- to 5-foliate leaves each. That is to say, 55% 

 abnormals as against 20% in the previous year — which 

 indicated a marked advance. 



But my hope of obtaining a leaf with mure than five 

 leaflets was not fulfilled. In spite of repeated search 

 I never found one. Nor did I obtain plants rich in four- 

 bladed leaves; for there were none with more than four 

 of them. 



Therefore I have since abandoned the hope of breed- 

 ing a race of four-leaved clover, corresponding to my 

 Trifoliwn pratcnse qidnqucfoHum, from this material. 



A striking feature of this experiment is the ajjparent 

 absence of a relation between the degree of al)normality 

 of the adult plants and that of the seedlings. For the 

 paucity of four-bladed leaves in the grown plants seems 

 incompatible with the abundance of multi foliate primary 

 leaves in the seedlings from which they grew. 



The failing of this relation has led me to the dis- 

 covery of a most remarkable connection between this 

 variability and the size of the seeds, for the smallest 

 seeds are those which give rise in the largest number to 

 compound primary leaves. 



Small seeds germinate somewhat later than larger 

 ones and also give rise to weaker plants. It had often 

 struck me that the selection of the most abnormal of the 

 seedlings was frustrated by the fact that many of the 

 indixiduals with compound primary leaves were too weak 

 to be planted out, or died soon after tlie process. It also 

 struck me that all the seedlings in a pan could not be 

 recorded at the same time. At first view the plants ap- 

 pear to germinate very regularly, and hundreds in the 

 same pan seem to unfold their leaves at the same moment. 



