HARRIS AND KUCHS : OBSERVATIONS ON POLLINATION. 



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I. -Aa, 21, lr; Ab, 1/, Br; Ba, 41, 4r ; Bb, 1/, Br. 

 II.— Aa, 8/, 13r; Ab, 131, llr; Ba, 1/, Bb, 11; B, 2Z, 3r. 

 III.— Aa, 4/, 2r; Ab, 2/, lr; Ba, 3r ; Bb, lr; B, 2r, 11. 



On the three plants, with 36 racemes bearing branches, there 

 were 18 branches which produced only one kind of flowers. 

 Of these branches, however, 15 bore only 1 liower each. 

 From this it will be seen that the flowers opening at the same 

 time on any one branch are not all either right- or left-handed. 

 In the large branches, A and B, the number of the two kinds 

 is quite evenly distributed ; in only one case- branch B of 

 plant III — is a large per cent, of the flowers alike. Even in 

 branches of the second denomination — Aa, Bb — flowers of one 

 kind occur exclusively, where more than one flower is found, 

 only in Ba of plant III. 



Tn addition to the above table, observations were made on 

 three plants to determine the regularity with which they bore 

 right- and left-handed flowers. On three successive mornings 

 the plants had produced : 



It will be noticed that when a marked excess of flowers of 

 one kind occurs one morning, a somewhat proportionate excess 

 of the other type occurs the following morning. This is of 

 course necessary if an equal number of the two types of flowers 

 are to be produced and, to a certain extent, to be maintained 

 on the same plant ; and is to be expected from the alternate 

 occurrence of the two types on opposite sides of the raceme. 



The flowers open early in the morning and remain open from 

 three to four days, depending somewhat upon the condition of 

 the weather. Some which were covered with cheese-cloth 

 " tents "' were noticed to remain open almost a week. At the 

 end of this period the corolla w T ilts and falls off, as does also 

 the pistil. The flowers seem to partially close at night. 



A limited series of experiments were made to determine if 



