74 



The Journal of Heredity 



all of the lateral kernels could be ger- 

 minated. The flowers of the central 

 spikelets are pollinated first. The 

 lateral ones usually are pollinated one 

 or two days later. 



Barley kernels six days of age are 

 very small. They have a very high 

 water content and when dried are 

 so small and brittle as to be dilificult to 

 handle. In the average kernel of Hann- 

 chen barley at this stage there are only 

 5 milligrams of dry matter, while at 

 maturity there are 35. The plants pro- 

 duced from these small kernels are very 

 slender and the first leaves are very 

 small. They are perfectly normal, 

 however, and develop into normal 

 plants which produce seed. When 

 grown under the conditions of this 



experiment the adult plants were not as 

 robust as those from mature seed, but 

 this may have been a result of their 

 having been transplanted. The seed- 

 lings were progressively taller and had 

 greater diameter of stem with the in- 

 crease of the age and size of seed, as 

 may be seen in Fig. 16. 



In 1921 a more accurate study was 

 made with Hannchen barley. Several 

 hundred flowers were emasculated with- 

 in a period of three or four hours. Two 

 days later these were hand-pollinated 

 and a record made of the exact time of 

 pollination. As barley pollen either 

 germinates or dies within a few minutes 

 after the anther is ruptured, the ages 

 of these kernels are known certainly 

 within one hour. As will be seen in the 



Results of experiments in germination of kernels of barley varieties harvested at different stages of 



development after flotvering 



