TRITICUM III 



Spikelets more than two-flowered, two or more fertile; terminal spikelet 

 developed; lateral teeth of glumes obtuse; palet remaining entire at 

 maturity. 

 Glumes as long or usually longer than lemma; palet about two-thirds 



as long as lenmia. T. polonicum (Polish wheat) . 

 Glumes shorter than lemma; palet nearly as long as lemma. 

 Rachis brittle, articulated, breaking at nodes when threshed, the seg- 

 ments remaining attached to spikelets; spikelets two-grained (some- 

 times three in spelt). 



Spikelets not set thickly on stem; arched on iimer side; adhering por- 

 tion of rachis thick, blunt; stem above with central canal. T. 

 spelta (spelt). 

 Spikelets set thickly on stem; flattened on inner side; adhering portion 

 of rachis slender, pointed; stem above, with exception of narrow 

 canal, filled with pith. T. dicoccum (emmer). 

 Rachis tenacious, not articulated, remaining entire in threshing; spikelets 

 usually more than two-grained. 

 Empty glumes sharply and broadly keeled to the base; lemma 

 bearded. 

 Spike with sides parallel or nearly so; glumes with a bloom, usually 

 glabrous; grain very hard, horny, long. T. durum (durum 

 wheat). 

 Spike short, crowded, long-ovate; glumes usually pubescent; grain 

 short, blunt and softer than that of T. durum. T. turgidum 

 (Poulard wheat). 

 Empty glumes keeled in upper half; rounded below (sometimes 

 slightly keeled in lower half); lemma sometimes bearded. 

 Spikes very short (rarely over 2 inches) ; very compact or crowded; 

 thicker at apex than center or base; grains small, short. T. 

 compactum (club wheat). 

 Spikes longer than 2 inches, open; sides usually parallel or nearly 

 so. T. (Bslivum (common bread wheat). 



The types of wheat fall into two natural groups, as to 

 attachment of lemma and palet to grain, as follows: 



1. "Naked wheats" in which the grain comes free from the 

 lemma and palet, and the rachis is tenacious {T. durum, 

 turgidum, compactum, cestivum, and polonicum). 



2. "Spelt wheats," in which the grain remains attached 

 to the lemma and palet, and the rachis is fragile {T. mono- 

 coccum, dicoccum, and spelta). 



