Partial J^ariability of Tricofyly. 447 



qiiently be entirely transformed. Branches of the second 

 order exhil)it no more tlian traces of the anomaly. 



If we apply this instance to the distrilmtion of tri- 

 cotylous seeds on a plant, we shcjnld conclude tliat the 

 lower part of the terminal inflorescence of the main stem 

 would produce the highest proportion of tricotylous seed- 

 lings ; but the flowers and fruits themselves are lateral 

 branches, and so the question arises, how far we are 

 justified in expecting this. 



In species like Oenothera and Antirrhinum, which 

 have a primary inflorescence rich in flowers and in seeds, 

 I have usually limited myself to this and, where possible, 

 to its lower and middle parts. In Heliehrysuni to the 

 flowerheads which open first, in Clarkia and Phaeelia to 

 as many of the earlier flowering branches as would pro- 

 vide a sufficient quantity of seed, and so on. The question 

 is whether these first fruits possess the same hereditary 

 capacity as would be found from the largest number of 

 fruits that could be gathered on the plant. 



With a view to determining this point I have insti- 

 tuted a number of subsidiary experiments. The answer 

 has been in the afi^rmati^'e throughout. Certainlv there 

 are small differences ; these, however, seldom fall out- 

 side the latitude of 5% which is the limit of observational 

 error. I shall now present the results of these experi- 

 ments in a condensed form. 



y\ first experiment was conducted with Oenothera 

 hirtella, which fertilizes itself in parchment bags with- 

 out artificial aid. In the summer of 1898 I planted out 

 seven tricotylous seedlings of one parent with a heredi- 

 tary value of 66% at distances of about a meter apart, 

 allowed them to branch freely and to develop into vig- 

 orous plants, enclosed the flowers in parchment bags and 



