154 BREEDING 



the hundredtli 11.100. But it is not necessary to 

 write the prefix indicating the year on the labels 

 themselves, because the only crosses harvested in a 

 given year are crosses made in that year ; this prefix 

 must, however, of course be written on the packet in 

 which the seeds are kept, because the packets may 

 be kept for many years. "Sowing numbers," which 

 are written on the pegs marking where peas are 

 sown, are distinguished by capital letters, A standing 

 for the first year of the experiment, B for the second, 

 and so on. But here, as in the case of the " mating 

 number," it is not necessary to write the prefix indicat- 

 ing the year on the pegs, because all the pegs in the 

 ground in any given year relate to seeds sown in that 

 year ; this prefix must, however, as in the case of 

 the mating prefix, of course, be written on the packets 

 in which the harvested seeds are kept. 



I strongly recommend anyone undertaking breed- 

 ing experiments not to use note books, but loose 

 sheets of squared paper. The year, in full, should 

 be written or, still better, stamped on one of the top 

 corners of every sheet. 



With regard, now, to the harvesting of the peas. 

 A plant should be pulled up, as a general rule, when 

 all its pods, save the uppermost one or two, are hard 

 and dry. The stem should be pulled off as far below 

 the level of the ground as the unaided fingers can 

 get ; it is necessary to do this because stems some- 

 times branch very near the ground, and the two 

 divisions of one plant might easily be harvested as 

 two plants if the precaution which I have advised 



