296 Maine Agricultural Experiment Station. 1919. 



The relative contribution of the butter-fat percentage of 

 the different lactations to butter- fat percentage over the first 

 five lactations is the same up to the fifth lactation. In the fifth 

 lactation the correlation coefficients would seem to indicate a 

 slightly less relative contribution of the higher test cows to the 

 five lactation butter-fat percentage than is the relative contribu- 

 tion of the lower test cows. In general, since the significance 

 of this correlation is only slight, the conclusion can be safely 

 drawn, that the factors which govern butter-fat percentage have 

 their regulatory power maintained in the same relative strength 

 throughout the life of the cow to the exclusion of any group of 

 factors acting within this life for short periods. 



ON VARIATION IN TARTARY BUCKWHEAT, FAGO- 

 PYRUM TATARICUM (L.) GAERTN.* 



The purpose of the present publication is to record the re- 

 sults of a study on a highly variable, ever-sporting race which 

 the writer has discovered in Fagopyrum tataricum. The race 

 with which this paper deals originated from commercial fruits 

 of Fagopyrum tataricum, Tartary buckwheat, also known as 

 India wheat, which had been grown in Maine. 



The more important observations recorded m this paper 

 may be summarized as follows. 



An ever-sporting race of Fagopyrum tataricum has been 

 isolated and its characters studied for 5 generations under vary- 

 ing conditions of environment. 



The variations here considered occur in the gynoecium, the 

 perigone, and the vegetative organs of this race. 



The variations in the gynoecium are characterized by the 

 production of supernumerary carpels. The number of carpels 

 per pistil was found to vary from 3 up as high as 25. Under 

 ordinary conditions of growth the number- of flowers with nor- 

 mal gynoecia is greater than or equal to the number of flowers 

 with abnormal gynoecia. Under conditions favoring the de- 

 velopment of abnormal flowers the variation is bilateral, and 



*This is an abstract from a paper by Jacob Zinn having the same 

 title and published in "Genetics," Vol. 4, No. 6. 



