BY THE SELECTION OF SOMATIC VARIATIONS. 13 



METHOD OF RECORDING RESULTS. 



To record fully the series of Coleus plants descended through vege- 

 tative propagation from any plant or any particular branch used as a 

 cutting, the pedigree method of culture has been used. It may be men- 

 tioned that the application of the pedigree-culture method to plants 

 propagated vegetatively is much simpler than its use in seed progenies, 

 the difficulties of which have been ably presented by Shull (1908). 



Each cutting was given a number which indicated its lineage. The 

 two plants serving as original parents were numbered 1 and 3, and the 

 first digit to the left in a number of any plant indicates the original 

 parent plant. For the progeny of plant No. 1, the second digit indi- 

 cates the particular main lateral branch from which the first cuttings 

 were taken, and the third digit is the number of the particular cutting. 

 Additional digits indicate successive plants grown later in the par- 

 ticular line of descent. Thus, plant 121 (I read these one-two-one, 

 etc.), 122, and 123 were grown from three cuttings taken from 

 branch No. 2 of plant No. 1. Plants 1211, 1212, and 1213 were from 

 cuttings of plant 121, while the numbers 12111, 12121, 12131, etc., 

 were given to plants of the next generation of cuttings. Thus the 

 number of any plant gives its complete pedigree since the experiments 

 were begun. Particular data regarding the cuttings and the plants 

 have been recorded on cards and filed in the manner of a card cata- 

 logue. This enables one to trace readily the inheritance of any varia- 

 tion through a series of generations and to compare different lines of 

 descent from any point in the culture. 



Following the suggestions of Webber (1903) and Shull (1912) the term 

 " clone" will be used in speaking collectively of all plants descended from 

 any one plant or branch. All the plants derived from plant No. 1 

 constitute a main clone, itself made up of numerous subclones. The 

 records of pedigree enable me to designate these as clone 11, clone 13, 

 clone 117, etc. I shall use the term "line of descent" to include the 

 different plants that were the parents of any one plant. The term 

 "generation" refers to the plants that were grown during the same 

 period. 



The observations here reported were made on successive generations 

 of pedigreed plants derived by vegetative propagation from two original 

 plants. These parent plants were alike when young in possessing a 

 color pattern that can be characterized as a mosaic of green, yellow, and 

 red, with the colors distributed as shown in figure 2. 



In referring to the color patterns, it seems best to the writer to use 

 terms that are sufficiently descriptive to make the matter concrete and 

 which at the same time are somewhat compact. The color of the 

 subepidermal tissues in the center of the leaf will be mentioned first, as 

 green or yellow; the color of the subepidermal tissues at the margin will 

 be mentioned next, as green or yellow, and last the character of the 



