378 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 



Again, when the northern turf -forming and the southern bunched form are grown 

 together their habits are more alike. Both will form a turf under proper moisture 

 conditions, and both when cultivated become tall and rank, similar to B. stricta 

 (PI. 69, B). 



In the publications of the United States Department of Agriculture this species 

 is usually referred to as "blue grama." The Spaniards of our southwest as well as of 

 Mexico refer to it simply as "grama," which they do not distinguish from similar 

 species. 



One of the most valuable characteristics of this species, as well as of some others of 

 the genus, is the short period of development. It is a 60 to 80 day grass. Upon the 

 Dakota prairies it produces fresh feed in late May and matures during the drought 

 of August. In southern Arizona and the highlands of Mexico it starts to grow about 

 the middle of July and matures with the close of the rainy and cooler season of late 

 September and early October. It grows in regions where it is cured by drought 

 and not by frosts, the effect being a dead herbage which retains much of its nutriment, 

 making good dry grazing during the winter season, the value of the grass being pro- 

 portionate to the dryness of the season. A rain after it has cured much reduces its 

 value. 



Shear's no. 813, Knowlton 140 and 141, Rydberg 3429, Williams 2143, Nelson 8307, 

 Merrill & Wilcox 447, Ward 47, and Griffiths 40 are typical of the prairie and northern 

 Rocky Mountain region. In unsodded regions from Colorado southward except at 

 higher elevations, it assumes more of the characters exhibited by specimens collected 

 by Wilcox at Fort Huachuca, in 1884, Mearns 2301, Metcalfe 698, Pringle 407, and 

 Townsend & Baker 257. Parish Brothers 1528, Herb. Colo. State Agr. College 3534 

 (distributed by N. Y. Bot. Gard.), Shehan 64, and Nealley from Texas, in 1887, are 

 mostly 1-spiked forms, and such forms occur throughout the range of the species. 

 They are to be looked upon as dwarfs. They appear to be very common in the lower 

 Sierras in California, at least they have been collected there a number of times. 



There is a very peculiar form of the species in the extreme western portion of northern 

 Texas. It differs from the common form mainly in its hairiness, but it occurs in 

 perfectly circumscribed patches among the other form and can be readily distinguished 

 at some distance. It has been seen twice north of Texline, but has never been col- 

 lected and has not been detected in any of the collections examined. So far as hairi- 

 ness is concerned, however, it is almost perfectly matched by a collection by Lind- 

 heimer (Herb. Texicana Exsic. no. 731) in the herbarium of the Missouri Botanical 

 Garden. This, however, is the large, robust, southern form which differs in general 

 appearance from the inhabitant of the plains. 



HERBARIUM SPECIMENS. 



Arizona: Blumer 1704, Chiricahua. Hitchcock 3656, Patagonia. Chase 5834, Flag- 

 staff. Hough 12, Moki Reservation and Little Colorado River. Leiberg 5927, 

 San Francisco Forest Reserve. Griffiths 3369 and 3370, Santa Rita Forest Reserve; 

 1863, Dragoon Mountains; 1552, Tucson; 1980, Pearce; 1905, Wilcox; 6108, Fort 

 Crittenden. Mac'Dougal 299, Flagstaff. Mearns 923, Bisbee; 1127, San Pedro 

 River; 2301, White Water; 2090, San Luis Mountains. Jones 4240, Bowie. 

 Lemmon 4641, 4642; northern Arizona, 427, 428. Tourney, Chiricahua Mountains; 

 20, Santa Catalina Mountains. Wilcox, Fort Huachuca. Griffiths & Thornber 

 225, Santa Rita Mountains; 264, Empire Ranch. 



California: Hall 7589, Santa Ana Canyon. Wilder 744, San Bernardino Mountains. 

 Grinwell 354, San Bernardino Mountains. Abrams 2100, San Bernardino County. 

 Parish Brothers 1528, Bear Valley, San Bernardino Mountains. Lemmon 5445. 



Colorado: Chase 5303, Manitou; 5290, Pikes Peak Region; 5393 and 5403, Harbert 

 Ranch, Las Animas County; 5346, near Starkville. Tidestrom 65a, Hugo. Shear 



