606 Mr Compton, On Right- and Left-Handedness in Barley. 



hardly change the real problem, which is the nature of the factor 

 determining the assumed accidental reversal. 



The twist of the first leaf is determined early in erabryogeny ; 

 so that the period during which the accidental influence must act 

 is quite limited. Thus it seems possible to conduct experiments 

 on the maturing ears by manipulating the orientation or the 

 environment : and this I hope to do in the future. It has been 

 thought worth w^hile to publish the above results, as marking a 

 definite step taken in analysing the problem under consideration. 



Finally, I wish to express my gratitude to Prof Bateson, who 

 suggested the investigation ; to Prof Bitfen, who has most kindly 

 supplied me with seed and with information ; to my parents and 

 sister, and to several friends at the Botanical Laboratory, who 

 have greatly assisted me in the labour of counting the seedlings ; 

 and to Mr F. J. M. Stratton who helped me with the curves. 



