792 



MISC. PUBLICATION 200, U. S. DEPT. OF AGRICULTURE 



Figure 1196. — Tripsacum floridnnum, X 1. (Hitch- 

 cock 686, Fla.) 



staminate glumes to vary greatly, 

 often in a single raceme. Occasional 

 specimens with glumes 10 to 11 mm. 

 long, soft or firm, are found also in 

 Iowa, Missouri, Kansas, Virginia, 

 Tennessee, and Oklahoma, the plants 

 not differing otherwise from the 

 species. 



2. Tripsacum floridanum Porter 

 ex Yasey. Florida gamagrass. (Fig. 

 1196.) Smaller than T. dactyloides in 

 all ways, commonly less than 1 m. 

 tall; blades mostly 1 to 4 mm. wide; 

 terminal and axillary racemes usually 

 solitary (rarely 2 or more). % — 

 Low rocky pinelands, southern Flor- 

 ida. 



3. Tripsacum lanceolatum Rupr. 

 Mexican gamagrass. (Fig. 1197.) 

 Resembling T. dactyloides; sheaths, 

 especially the lower, sometimes his- 

 pid; blades often hispidulous on the 

 upper surface; racemes more slender 

 with smaller spikelets than in T. 



Figure 1197. — Tripsacum lanceolatum, X 1. (Lem- 

 mon, Ariz.) 



dactyloides, the terminal racemes usu- 

 ally 3 to 5; staminate spikelets mem- 

 branaceous, one of the pair distinctly 

 pediceled. % ( T. lemmoni Yasey.) 

 —Rocky hills, Huachuca and Mule 

 Mountains, Ariz.; Mexico to Gua- 

 temala. 



167. EUCHLAfiXA Schrad. 

 Teosinte 



Staminate spikelets as in Zea; 

 pistillate spikelets solitary on oppo- 

 site sides, sunken in cavities in the 

 hardened joints of an obliquely ar- 

 ticulate rachis, the indurate first 

 glume covering the cavity; second 

 glume membranaceous, the lemma 

 hyaline. Spikes infolded in foliaceous 

 spathes or husks, 2 to several of these 

 together enclosed in the leaf sheaths. 

 Robust annuals and perennials with 



