HOWARD AND HOWARD. 39 



A similar sharp segregation was observed in some of the crosses 

 made at Pusa in 1906, but the figures were not published as one of the 

 parents used was not a pure line. 



Some nitrogen determinations 1 were made of the various classes 

 in the F 2 , and these are given in the table above. It will be seen 

 that both parents are high in nitrogen, and that in the second 

 generation there is no connection between translucency and high 

 nitrogen content, but that both these characters are inherited 

 independently. Plants with low and high nitrogen occur in all 

 the classes. It is proposed to study this cross in detail from the 

 point of view of the inheritance of strength and free-milling 

 qualities. 



Shattering of the Ear. 



In India., one of the important characters of wheat from the 

 economic standpoint is the power of holding the grain in the ear when 

 the wheat is ripe. At harvest time the temperature is high, the air 

 exceedingly dry and high winds are common. Moreover, it is the 

 custom to allow the wheat to become dead ripe before it is cut, and 

 owing to scarcity of labour at harvest time it often remains standing 

 in the fields long after it is ripe. Under these circumstances many 

 wheats drop their grain and a great loss of wheat results. In the 

 improvement of Indian wheat any tendency to shed grain is a fatal 

 defect in a new wheat, and several otherwise excellent types have 

 had to be discarded by us on this account. In one of our crosses 

 a distinct segregation in the F 2 was noticed as regards the shattering 

 of the ear, and the 15 : 1 ratio was perfectly distinct. Two factors 

 must therefore have been present, one of which it is likely to be found 

 in Pusa 6 as this line has a tendency to shed its grain, but the shat- 

 tering of many plants in the F 2 was much greater than in Pusa 6. 



The details relating to the F 2 of the cross in cpuestion are given 

 in the following table : — 



Name of cross. , , °". . \ t ° n - Shatterini:. liatio. 



of plants. shattering. 



American Club x Pusa 6 (2) 215 12 203 1: 16-9 



1 Wc arc indebted to Dr. Leather, Imperial Agricultural Chemist, for these nitrogen 

 determinations. 



