BOTANICAL CHARACTERS t i 5 



P»reed. 

 Iowa Silver-mine 

 Ladysmith 



Increase in number of rows is often accompanied by a cor- 

 responding decrease in the breadth of the individual grains. 

 But this is not always the case ; much depends on the thick- 

 ness of the cob; the grains on a 16-row ear are sometimes 

 broader than those on a 12-row ear of the same breed, if the 

 cob of the former is thick while that of the latter is thin. 



Increase in number of rows means a larger number of 

 grains, but it does not necessarily follow that it is accompanied 

 by increase in amount of grain produced. In Golden King 

 (yellow dent), the best 14-row ears gave more grain than the 

 best 12-row, but some of the io-row also gave more than the 

 12-row. In Yellow Horsetooth (yellow dent), the ten best 

 14-row ears also gave more grain than the corresponding 

 [2-rowears, but the ten poorest ears of the latter gave more 

 than the ten poorest 14-row ears. In Yellow Hogan (yellow 

 dent), the seven best 14-row ears gave more grain than the 

 seven best 16-row ears {Burtt-Davy, 18). 



The same number of rows does not give equally good 

 returns in all breeds alike. Each breed seems to have an 

 optimum number, which gives the best results in weight, 

 shape, and size of grain, above or below which deterioration 

 commences. 



In some breeds the rows occur in distinct pairs ; the rows 

 are then described as distichous. 



86. Tzvisted Rows. — The occurrence of a twist in the rows, 

 either to left or right (Figs. 58 and 59), is a common feature. 

 It is often confined to the upper portion of the ear, but may 

 start from near the base. It is an undesirable character, as it 

 tends to the development of irregular grains. This twisting 

 appears to be in some way associated with the development 

 of the number of rows. Out of a number of cases examined 

 the following figures were obtained (lhtrtt-Davy, 18J: — 



Row numbers. Left twist. Right twist. Ears examined. 



14 17 = 5g'6 per cent 12 = 41-4 per cent 29 



18 12 = 6o - o ,, 8 = 4<ro ,, 20 



16 Rows very straight, no twist. 



2 9 = 59'3 P er cent 2 ° = 4°'7 P er cent 49 



8* 



