THE GRASSES OF BRITISH HONDURAS AND THE PETEN, GUATEMALA 189

grown together; spikelets awnless, the sessile one brown, globose with an
alveolate first glume, the pedicellate staminate, green, the first glume lancco-
late, scabrous. A common weed in open grassy places in tropical regions.
 BRITISH HONDURAS. Toledo District: Toledo, Peck 653.

 57. TRIPSACUM L.
Blades I to 2 cm. wide.. .......1. T. dactyloides
Blades 3 to 6 cm. wide ........2. T. latifolium

1. Tripsacum dactyloides (L.) L. Syst. Nat. ed. 10. 2: 1261. 1759.
 Differing from T. latifolium chiefly in having narrower blades, 1 to 2 cm.
wide. Open ground, eastern United States and the West Indies to Para-
guay and Bolivia.
 GUATEMALA. Pet6n: La Libertad, top of limestone hill, Lundell 2836
 (specimen without inflorescence).

2. Tripsacum latifolium Hitchc. Bot. Gaz. 41: 294. 1906.
 Perennial; culms coarse, 2 to 4 m. tall; blades flat, long-acuminate, nar-
rowed below into a long petiole-like base, 70 cm. to more than 1 m. long.
2.5 to 6 cm. wide, the margins serrate; inflorescence moncecious, composed
of one or more spikelike racemes, the pistillate spikelets below, embedded in
the articulate rachis, the staminate ones above. Rocky slopes, Mexico and
Central America.
 BRITISH HONDURAS. El Cayo District: Mountain Pine Ridge, Bartlett
 11888. Toledo District: Yeacos Lagoon, Peck 703.

 58. ZEA L.
 1. Zea mays L. Sp. PI. 971. 1753. xiim; M.uz.
 Annual; culms coarse, tall, with broad, flat, recurved blades; staminate
 inflorescence terminal, composed of numerous, drooping, one-sided, spikelike
 racemes; pistillate inflorescence axillary, the spikelets arranged in rows
 around a thickened, woody axis, the whole enclosed in numerous leaf-like
 bracts.
 Commonly cultivated in warm and temperate regions.