382 



CONTRIBUTIONS FROM THE NATIONAL. HERBARIUM. 



densely pubescent, 4-toothed, with 3 scabrous equal awns, about 2 mm. long; palet 

 4-toothed, 2-awned, pubescent on the edges only, about 2.5 mm. long; rudiment con- 

 sisting of 3 scabrous, equal awns, about 4 mm. long, together with two or three small 

 scales upon a stipe about 1 mm. long, bearing a tuft of long hairs at each end; caryopsia 

 obovate, pointed at both ends, about 1.3 mm. long, less than 0.5 mm. wide, the 

 scutellum covering nearly the entire ventral surface, the dorsal surface convex. 

 (Plate 73, A. Figure 37.) 



The specimens cited in the original description are undersized and can scarcely 

 be called cespitose. They differ, therefore, very decidedly from the large speci- 

 mens of the Santa Rita Mountains. They also differ decidedly in color, my speci- 

 mens from southern Arizona 

 being much lighter. Woo- 

 ton's no. 6033 is especially 

 dark colored, but this is 

 easily accounted for by the 

 abnormal rainfall of the sea- 

 son in which it was collected . 

 The rains appeared very late 

 that year and continued into 

 the cool season. Grasses 

 often show this excessive col- 

 oration when subjected to 

 cooler nights than normal, 

 either when growing later in 

 season than usual or at high 

 altitudes. The type speci- 

 mens are so diminutive that 

 they are really not at all rep- 

 resentative of the species as it 

 is commonly found . Pringle 

 413, Nealley 265, Lemmon 

 4638, well represent the com- 

 mon form of this species. 



HERBARIUM SPECIMENS. 



Arizona: Mearns 1121^, San 

 Pedro River, Mexican 

 Boundary Line. Nealley 

 265, Oracle. Lemmon 

 426 and 4638, "S. E. 

 Arizona." Griffiths & 

 Thornier 206, Santa Rita 

 Mountains. Griffiths 

 1819, 3415, Mescal. 



New Mexico: Cockerell 16, 

 Jarilla Junction. 



Texas: Scribner in 1887. 

 Mexico: Schafner 1019 and 157, San Luis Potosi. Pringle 413, Chihuahua. Wilkinson, 

 Santa Eulalia Mountains, Chihuahua. Parry & Palmer 943J, San Luis Potosf. 



11. Bouteloua barbata Lag. 



Bouteloua barbata Lag. Var. Cienc. 2 4 : 141. 1805. This name has dropped out of 

 recent literature, although it was correctly interpreted by Ruprecht, Roemer and 



Explanation of Plate 73. — A. A clump of Bouteloua parryi consisting of several plants with those 

 around removed. In situations like this, where many plants are found together, the habit is different from 

 that wherein it grows in more isolated scattered bunches. B. An unusually large isolated tuft of Bouteloua. 

 barbata, Adamana, Arizona. 



Fig. 37 '.—Bouteloua ■parryi. a, S pikelet; b, c, lemma and palet of first 

 floret; d-f, rudimentary second, third, and fourth florets; g, two 

 views and cross section of caryopsis. a, Scale 7.5; b-g, scale 12.5. 

 a-t, From Griffiths 7277; g, from Wooton 3065. 



