PLANT HYBRIDIZATION BEFORE MENDEL 105 



the first generation was followed in the second (the F^ for the 

 seed-coats) by segregation, which is recorded by Laxton, to the 

 effect that "in shape, the peas were partly indented ; but a few 

 were round." (4b, p. 11.) 



The lack of a proper ratio in this case, of 3 round to 1 in- 

 dented, was probably due to the small number of plants involved. 



In 1868 (the Fo for flower and seed-coat color), Laxton says: 



"Some of the plants had light-colored stems and leaves; these all 

 showed white flowers and produced round white seeds. Others had purple 

 flowers, showed the purple on the stems and at the axils of the stipules, 

 and produced seeds with maple, grey, purple-streaked, or mottled, and 

 a few only, again, with violet-colored envelopes." (4b, p. 11.) 



It is further stated that: 



"The pods on each plant, in the majority of instances, contained peas 

 of like characters ; but in a few cases the peas in the same pod varied 

 slightly, and in some instances a pod or two on the same plant contained 

 seeds all distinct from the remainder." (4b, p. 11.) 



It is reported that the white-flowered plants of the Fo were 



"generally dwarfish, of about the height of 'Ringleader,' but the colored- 

 flowered sorts varied altogether as to height, period of ripening, and color 

 and shape of seed." (p. 11.) 



There would appear to be here some evidence of partial link- 

 age of height with white flower and seed-coat color. 



The outline of the results of Laxton's cross, stated in modern 

 terms, is as follows : 



1866 Parents 



''Ringleader' "Maple' 



Flowers — white Flowers — purple 



Seed-coats — white Seed-coats — "maple" 



Cotyledons — round Cotyledons — indented 



Height — 2i^ feet Height — taller than "Ringleader" 



Progeny 



1866. F, (for cotyledons) 

 Cotyledons — round 



1867. F, (for flower color and seed-coat color) 

 Flowers — purple 



Seed-coats 



(1) (2) ("a few") 



Maple or brownish-streaked Violet or deep purple 



Cotyledons — partly indented ; a few round 

 Height — tall 



