20 



BTJLLETIlSr 692, U. S. DEPAETMENT OP AGRICULTURE. 





Fig. 6.— Seeds of Rhode Island iDent {Agrostis 

 tenuis), enlarged and natural size. In seeds 

 a and 6 the palet is not wrinkled. In seeds 

 c and d the palet is wrinkled and translucent. 

 In seed e the transparent, closely adherent 

 palet is obscured against the darker grain. 

 (The natural size is shown at/.) 



and three-fourths the length of the lemma, rarely but half the 

 length of the grain, obscurely striate, translucent, showing the 

 grain, more or less adherent to the grain, rarely wholly adherent and 

 transparent and therefore obscured till separated from the grain 



(fig. 3, 3); veins of the palet often 

 distinct, sometimes scarcely evident ; 

 grain oblong in outline, often robust, 

 mostly reddish brown and finely 

 wrinkled, dry and mealy when 

 crushed under slight pressure (fig. 5). 



SEED OF RHODE ISLAND BENT (aGROSTIS 

 TENUIS SIBTH.; AGROSTIS VULGARIS WITH.). 



Lemma 0.04 to 0.07 of an inch in 

 length, ovate-lanceolate to narrowly 

 lanceolate in outline, narrowly point- 

 ed at the apex, exceeding the grain 

 by one-fourth or less of its length, 

 not glistening, the upper half or more 

 of the lemma translucent and silvery 

 white, opaque toward the base; the 

 surface of the lemma glabrous and 



finely striate longitudinally; the apex of the lemma usually distinctly 



three angled; an aborted awn occasional from near the apex or 



rarely not lower than the middle of the lemma, straight, not spirally 



twisted, rarely equaling the apex of the lemma, such awn-bearing 



lemmas sometimes four angled at the apex ; seeds 



of some plants all or nearly all bearing similar 



awns, each awn arising between one-fourth and one- 

 third the length of the lemma from its base, the 



awn bent near the apex of the lemma and spirally 



twisted below the bend; the lemmas thus awned 



four veined at the apex (fig. 7) ; palet sometimes 



not wrinkled, semitranslucent and striate, rarely 



equaling the grain, usually clearly shorter than 



the grain, between one-half and two-thirds the 



length of the lemma, or often scarcely exceeding 



half the length of the grain, usually wrinkled and 



partially adherent to the grain, often wholly ad- 

 herent and transparent and therefore obscured 



till separated from the grain; veins of the palet commonly wanting; 



grain slenderly oblong in outline, dry and mealy when crushed. 



(Figs. 6 and 7.) 

 Compared with seeds of redtop, the seeds of Rhode Island bent are, 



in general, more slender, smajler. less glistening, and lighter colored; 



Fig. 7.— Seeds of the 

 awned form of Rhode 

 Island bent {Agrostis 

 tenuis). (Enlarged.) 



