MENDEL 



which were used in the experiments 

 the following are dominant: 



1. The round or roundish form of 

 the seed with or without shallow de- 

 pressions. 



2. The yellow colouring of the seed 

 albumen [cotyledons]. 



3. The grey, grey-brown, or leather- 

 brown colour of the seed-coat, in asso- 

 ciation with violet-red blossoms and 

 reddish spots in the leaf axils. 



4. The simply inflated form of the 

 pod. 



5. The green colouring of the un- 

 ripe pod in association with the same 

 colour in the stems, the leaf-veins and 

 the calvx. 



6. The distribution of the flowers 

 along the stem. 



7. The greater length of stem. 



With regard to this last character it 

 must be stated that the longer of the 

 two parental stems is usually exceeded 

 by the hybrid, a fact which is possibly 

 only attributable to the greater luxuri- 

 ance which appears in all parts of 

 plants when stems of very diff^erent 

 length are crossed. Thus, for instance, 

 in repeated experiments, stems of 1 ft. 

 and 6 ft. in length yielded without ex- 

 ception hybrids which varied in length 

 beu\'een 6 ft. and 7 Yz ft. 



The hybrid seeds in the experiments 

 with seed-coat are often more spotted, 

 and the spots sometimes coalesce into 

 small bluish-violet patches. The spot- 

 ting also frequently appears even when 

 it is absent as a parental character. ^- 



The hybrid forms of the seed-shape 

 and of the albumen [colour] are de- 

 veloped immediately after the artificial 

 fertilisation by the mere influence of 

 the foreign pollen. They can, there- 

 fore, be observed even in the first year 

 of experiment, whilst all the other 

 characters naturally only appear in the 



12 [This refers to the coats of the seeds 

 borne by F^ plants.] 



following year in such plants as have 

 been raised from the crossed seed. 



[Fo] THE GENERATION [bRED] 

 FROM THE HYBRIDS 



In this generation there reappear, to- 

 gether with the dominant characters, 

 also the recessive ones with their pecu- 

 liarities fully developed, and this 

 occurs in the definitely expressed aver- 

 age proportion of three to one, so that 

 among each four plants of this genera- 

 tion three display the dominant char- 

 acter and one the recessive. This relates 

 without exception to all the characters 

 which were investigated in the experi- 

 ments. The angular wrinkled form of 

 the seed, the green colour of the albu- 

 men, the white colour of the seed- 

 coats and the flowers, the constrictions 

 of the pods, the yellow colour of the 

 unripe pod, of the stalk, of the calyx, 

 and of the leaf venation, the umbel-like 

 form of the inflorescence, and the 

 dwarfed stem, all reappear in the nu- 

 merical proportion given, without any 

 essential alteration. Transitional forms 

 were not observed i?i any experijfient. 



Since the hybrids resulting from re- 

 ciprocal crosses are formed alike and 

 present no appreciable diff^erence in 

 their subsequent development, conse- 

 quently the results [of the reciprocal 

 crosses] can be reckoned together in 

 each experiment. The relative numbers 

 which were obtained for each pair of 

 diflFerentiating characters are as fol- 

 lows: 



Expt. 1. Form of seed.— From 253 

 hybrids 7,324 seeds were obtained in 

 the second trial year. Among them 

 were 5,474 round or roundish ones and 

 1,850 angular wrinkled ones. There- 

 from the ratio 2.96 to 1 is deduced. 



Expt. 2. Colour of albumen.— 258 

 plants yielded 8,023 seeds, 6,022 yel- 

 low, and 2,001 green; their ratio, there- 

 fore, is as 3.01 to 1. 



In these two experiments each pod 



