EXPERIMENT WITH A PLANT 153 



put forward by Mendel will be dealt with in the next 

 chapter. 



When the petals of the pollinated flower have been 

 folded into their place a label should be tied round 

 the stalk of the flower by means of an 8-shaped loop, 

 one half of which encircles the flower stalk, and the 

 other the main stem. A number, corresponding to 

 a number in a record of all the necessary details with 

 regard to the cross, should then be written on the 

 label. A label bearing the same number, preceded 

 by " f . of " (meaning " father of "), should be tied 

 in the same manner round the stalk of the flower 

 which furnished the pollen with which the cross 

 was made. And nothing further need be done to 

 it until the autumn when the pod is hard and dry 

 (see Fig. 33), when the seeds can be taken out of 

 it and put into a packet with the number on the 

 label tied round the flower in the summer, written 

 on it. In order to render the possibility of error as 

 remote as possible, it is well to cut off the label and 

 put it into the packet with the seeds. 



It is convenient to describe here a system of 

 keeping the records of my experiments which I have 

 found to work very well. I have two classes of 

 numbers from 1 onwards in each year — " mating num- 

 bers " and " sowing numbers." " Mating numbers," 

 which are written on the labels tied round the crossed 

 flowers, and on those tied round the plant which 

 furnished the pollen, are distinguished by the year 

 in which the cross is made ; for instance, the first 

 cross I shall make this year, 1911, will be 11.1, and 



