EXPLANATION OF FORM. 13 



grain in the head or in every head is infected the percentage is 100, 

 and zero when the plant or plat is entirely free from smut. 



Head {field notes). — The term beardless is applied to those heads 

 the flowering glumes of which bear no awns longer than 1 centimeter; 

 partly hearded where some of the flowering glumes bear awns longer 

 than 1 centimeter while others bear awns much shorter, and bearded 

 when all the flowering glumes bear awns longer than a centimeter. 

 The terms erect, leaning, and nodding apply to the way the head is 

 borne by the stem at or after maturity. The dates of appearance, 

 flowering, and maturing need no explanation. 



The terms shattering badly, rued! inn, and none apply to the ability of 

 the glumes to hold the grain after maturity. These are only compar- 

 ative terms, as this is a quality difficult of actual measurement, but it 

 is an item of great importance in all the large wheat-producing regions 

 and should be most carefully considered. 



Head {laboratory notes). — The length measurement should be taken 

 from the lowest joint of the head to the tip of the apical flowering 

 glume, not counting the awn if one is borne by this glume. The 

 terms very open (PI. Ill, fig. 2, No. 1), open, medium, compact, and 

 crowded (PI. Ill, fig. 2, No. 2) apply to the way the spikelets are 

 borne in the head. These are relative terms, since the size of the 

 spikelet has some influence in this matter, making the statement of 

 this quality by giving the distance between the joints unsatisfactory. 



Under shape of spike, the term tapering toward apex should be 

 applied to those which taper gradually from about the middle or 

 below. Tapering both ways should be applied to those spikes which 

 are spindle-shaped or larger in diameter at the middle than at either 

 end. Uniform (PI. Ill, fig. 2, No. 1) applies to those spikes which 

 are very nearly the same diameter throughout their length. Clubbed 

 (PI. Ill, fig. 2, No. 2) should be applied to those spikes which are 

 larger at the tip than below. The term tip acute (PI. Ill, fig. 2, 

 No. 1) is applied to those spikes which terminate with one or two 

 undeveloped spikelets, and tip blunt (PI. Ill, fig. 2, No. 2) to those 

 having terminal spikelets well filled out; base abrupt to those having 

 basal spikelets well developed, and base tapering to those having the 

 basal spikelets very small or undeveloped. Square applies to those 

 spikes the diameters of which through and across the spikelets are 

 about the same, and fattened with spikelets (PI. Ill, fig. 2, Nos. 5 

 and 6) to those spikes which have the diameter through the spike- 

 lets smaller than the diameter across the individual spikelet, the con- 

 dition commonly found in Triticum sestwum; while flattened across 

 spnkelets (PI. Ill, fig. 2, Nos. 3 and 1) applies to those spikes having 

 the diameter through the spikelets greater than that across them, the 

 condition common to the varieties of Triticum durum. The terms 

 straight and slightly curved need no explanation. 



The color terms are asrain relative. 



