HITCHCOCK—MEXICAN GRASSES. 195 
Glumes not scarious- 
margined. 
Sterile lemmas at 
base of spike- 
let several.... 114. Unroxa (p. 370). 
Sterile lemmas at 
base of spike- 
let none. (See 
continuation.) 
(CONTINUATION. ) 
Lemmas keeled, awnless.........-------------+-5- 118. Poa (p. 372). 
Lemmas convex, or keeled toward the summit. 
Rachilla and callus villous..............--..--- 119. GRAPHEPHORUM (p. 376). 
Rachilla and callus not villous, sometimes pubes- 
cent. 
Nerves of lemma prominent, parallel........ 120. PANICULARIA (p. 376). 
Nerves of lemma not prominent, often faint, 
converging at the summit. 
Spikelets in a mostly simple raceme; 
palea pectinate-fringed.......... 123. BracHypopium (p. 383). 
Spikelets panicled; palea not pectinate- 
fringed. 
Lemmas not toothed at summit, usu- 
ally awned, the awn terminal. 121. Festuca (p. 376). 
Lemmas toothed at summit, the awn 
from between the teeth...... 122. Bromus (p. 380). 
ANNOTATED LIST OF THE SPECIES. 
1. EUCHLAENA Schrad. Sem. Hort. Goettingen 1832; reprinted in Linnaea 8: 
Litt. 25. 1833. 
1. Euchlaena mexicana Schrad. Sem. Hort. Goettingen 1832; reprinted in Linnaea 
8: Litt. 25. 1833. TEOSINTE, 
Type locality, ‘‘Mexico.”’ 
Ranae: Durango to Jalisco, Oaxaca, and Chiapas. 
HERBARIUM SPECIMENS: 
Duranco: Durango, along water ditches, Palmer 743 in 1896. 
Jauisco: Zapotlan, prairie along railroad, Hitchcock 7146. 
Micnoacdn: Queréndaro, rocky hills, Pringle 4319. 
Oaxaca: San Augustin, in arena fluvii exsiccati prope mare Pacificum, Lieb- * 
mann 548. 
Curapas: Tuxtla Gutiérrez, Collins & Doyle 102. 
2. TRIPSACUM L. Syst. Nat. ed. 10. 1261. 1759. 
KEY TO THE SPECIES. 
Blades narrow, usually less than 12 mm. wide; plants usually 1 to 
1.5 meters high. ............-.....-..-2-2-2-22------------ 1. T. lanceolatum. 
Blades wide, usually 5 to 7 cm.; plants tall and stout as much as 
2.8 meters high. 
Sheaths glabrous. ............2. 02.202 e cece eee eee eee eee eee 2. T. laxum. 
Sheaths hispid... ..............- 22 cece eee reece ence cece eee 3. T. pilosum. 
