66 



Tbiodia, H. Br. (Tricuspis, Beauv.) 



Spikelets several to many flowered in a strict spike-like or an 

 open spreading panicle, some of the upper flowers male or imper- 

 fect ; outer glumes' keeled, acute or acutish, awnless ; flowering 

 glumes imbricated, rounded on the back, at least below, hairy or 

 smooth, three-nerved, either mucronate, three-toothed or three-lobed 

 at the apex, or obscurely erose, often hardened and nerveless in 

 fruit ; palet broad, prominently two-keeled. 



1. T. acuminata, (Tricuspis acuminata, Munro.) Texas to Ai-i- 



zona. 



2. T. albescens, (Tricuspis albescens, Munro.) Texas to Arizona. 



3. T. ambigua, (Tricuspis ambigna, Chap.) Texas to Arizona. 



4. T. avenacea, H. B. K. Texas to Arizona. 



5. T. eragrostoides, Vasey and Scribner. Florida. 



6. T. mutica, (Tricuspis mutica, Torr.) Texas to Arizona. 



7. T. pulchella, H. B. K. Texas to Arizona. 



T. pulchella, var. parviflora, Vasey. Texas to Arizona. 



8. T. seslerioides, (Tricuspis, Torr.) New York to Texas. Tall 



Red top. 



This grass grows from 3 to 5 feet high. The culms are very 

 smooth ; the leaves are long and flat, the lower sheaths hairy or 

 smoothish. The panicle is large and loose, at flrst erect, but finally 

 spreading widely. The branches are single or in twos or threes be- 

 low, and frequently 6 inches long, divided, and flower-bearing above 

 the middle. The spikelets are on short pedicels, three to four lines 

 long, and five or six flowered. The outer glumes are shorter than 

 the flowers, unequal and pointed ; the flowering glumes are hairy 

 toward the base, having three strong nerves, which are extended 

 into short teeth at the summit. It is a large and showy grass when 

 fully matured, the panicles being large, spreading, and of a purplish 

 color, It grows in sandy fields, and on dry sterile banks, from New 

 York to South Carolina, and westward. This is eaten by cattle 

 when it is young, but the culms are rather harsh and wiry and not 

 relished by them. It is, however, cut for hay, where it naturally 

 abounds. 



9. T. stricta, (Tricuspis, JVuM.) Texas to Arizona. 



10. T. Texana, S. W. (Tricuspis, Thurb.) Texas to Arizona. 



11. T. trinerviglumis, (Tricuspis, Benth.) Texas to Arizona. 



