Mr Gompton, On Right- and Left- Handedness in Barley. 495 



On Right- and Left- Handedness in Barley. By R. H. 

 CoMPTON, B.A., Frank Smart Student of Gonville and Caius 

 College. 



[Eeceived 6 June 1910.] 



A seed of barley produces on germination a tubular sheath 

 through which the first green leaf emerges. This first leaf is so 

 folded that one margin overlaps the other, at first throughout nearly 

 its entire length ; later on, after more leaves have been produced, 

 only the lower sheathing portion retains the original fold. In 

 some cases the right-hand margin overlaps, in others the left-hand. 

 A convention is necessary in the use of these terms : the one used 

 here is illustrated by figure 1. The observer is supposed to be 



First 



" LEAF 



SHLfiTH — 





Fig. 1. 

 Diagram of the two " stereo-isomeric " forms of Barley seedling. 



standing in the axis of the plant, facing outwards through the 

 open side of the leaf, and folding one hand over the other to 



