478 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM, 
22. Panicum pampinosum Hitche. & Chase. 
Panicum pampinosum Hitche. & Chase, Contr. U. 8. Nat. Herb. 15: 66. 1910. 
Culms 15 to 40 cm. high, ascending from a decumbent base or widely spreading. 
DISTRIBUTION. 
Open ground and depressicns in mesas, 
southwestern United States to central 
Mexico. The type specimen from Ari- 
zona. 
CHIHUAHUA: Mifiaca, Hitchcock 7751, 
7756. 
GUANAJUATO: Acambaro, Hitchcock 
cae x 6952. 
Fig. 35.—Distribution of P. pampinosum. 
, 23. Panicum decolorans H. B. K. 
Panicum decolorans H. B. K. Nov. Gen. & Sp. 1: 100. 1816; Contr. U. S. Nat. Herb. 
15: 66. 328. 1910. 
DISTRIBUTION. 
Fields and waste ground, central Mexico. 
The type specimen from Querétaro. 
San Luis Potosi: Cardenas, Amer. Gr. 
Nat. Herb. 29. 
QUERETARO: Querétaro, Basile 51, 52; 
Hitchcock 5822, 5864. 
PuEBLa: Tehuacan, Hitchcock 6057. 
Fig. 36.—Distribution of P. decolorans. 
24. Panicum stramineum Hitchce. & Chase. 
Panicum stramineum Hitche. & Chase, Contr. U. S. Nat. Herb. 15: 67. 1910. 
This species was described as having glabrous (or sometimes ciliate) blades. Later 
collections show that the blades are sometimes sparsely papillose-pilose. 
DISTRIBUTION. 
Rich bottom lands and damp soil, Arizona, 
to Michoacén. The type specimen from 
Guaymas. 
Sonora: Guaymas, Palmer 168a and 
206 in 1887. 
Smnatoa: Culiacdn, Palmer 1538 in 
1891. Between Rosario and Aca- 
poneta, Rose 1878, 1883. 
Durango: Durango, Hitchcock 7658. 
Trpic: Between Concepcién and Acaponeta, Rose 1889. Acaponeta, Rose 3281. 
MicHoacan: Morelia, Arséne 60, 2985. 
GuERRERO: Lagunillas, Langlasse 263.1 
Fig. 37.—Distribution of P. straminewm. 
1 Tn the Revision this specimen was doubtfully referred to P. filipesScribn. (Contr. 
U.S. Nat. Herb. 15: 74. 1910). 
