Studies of Teratological Phenomena. 97 



containing moderately rich soil. Often these pans were crowded with 

 young plants, but they did not remain in such quarters long enough to 

 become stunted. In pricking out plants, naturally and unconsciously, 

 the best seedlings were selected, though this was not always the case, 

 especially when seed was scarce. Variation between the plants became 

 greatest after they had been pricked off into flats, and when final 

 transplantation time arrived, there were some more or less stunted 

 individuals, but all were usually planted. The normals (402) were 

 always subjected (in my own work) to the same treatment as the 

 fasciated race. Plants were grown in a variety of environments, and 

 in order to show the constancy of the race under these environments. 

 Table 2 was constructed. The number of leaves per plant is extremely 

 variable, as evidenced repeatedly in a leaf count of the progeny of a 

 single selfed plant, when all had been grown under the same conditions. 

 124 plants from selfed seed of a single 402 plant, grow^n under shade 

 in Connecticut in 1911, gave an average of 19 •65 leaves per plant, 

 with a range of variability between 14 and 24, and a mode of 20. In 

 1908, under about the same conditions, 99 plants from selfed seed of 

 the original mutant were grown, and leaf counts made by J. S. Dewey, 

 gave an average of 69*7 leaves per individual, with a range of 

 variability between 30 and 133 and a mode of 57. Included in Table 3 

 are abnormal segregates, but these as far as I can judge, are 

 indistinguishable from the pure abnormal race. The range of variabihty 

 in the number of leaves in different years is well shown in Table 2. 

 301 — 309 consisted of 148 progeny grown at Bloomfield, Conn., from 

 selfed seed of nine of Dewey's 1908 plants. 301 — 1 and 303 — 1 were 

 selections from the 1909 cultures, the progeny of which were grown 

 under field conditions at the Bussey Institution in 1910. X is the 

 progeny of a single selfed plant of Dewey sport (genealogy lost) grown 

 in the Bussey greenhouse, the winter of 1909 — 1910. The 1911 

 selections were all grown under the same environment at the Bussey 

 Institution. The same is true of the 1912 cultures, except that the 

 five 301 — 1 plants were neglected before transplantation, and given 

 poor soil in field cultures. These data are subject to the criticism that 

 in a study of environmental effect on plants, seed from the same, 

 instead of from different plants, should be used. But this criticism is 

 probably invalid here, because the fasciated race is a pure line upon 

 which selection (White, 1913) seems to have no effect. So for puiT)oses 

 of comparison, seeds of different individuals of a pure line have the 



Induktive Abstämmlings- und Vererbungslehre. XVI. 7 



