794 



MISC. PUBLICATION 200, U. S. DEPT. OF AGRICULTl'UK 



broad flat blades, terminal panicles 

 of staminate spikelets, and axillary- 

 spikes of pistillate spikelets. Type 

 species, Euchlaena mexicana. Name 

 from Greek eu, well, and chlaina, 

 cloak, alluding to the husks hiding 

 the pistillate inflorescence. 



1. Euchlaena mexicana Schrad. 

 Teosinte. (Fig. 1198.) Tall annual, 

 resembling maize, the culms branch- 

 ing at base, 2 to 3 or even 5 m. tall; 

 blades as much as 8 cm. wide. 

 — Occasionally cultivated in the 

 Southern States for green forage; 

 Mexico. Closely related to maize and 

 readily hybridizing with it. 



2. Euchlaena perennis Hitchc, 

 Mexican teosinte, a perennial spe- 

 cies from Mexico, is cultivated at the 

 substation of the agricultural college, 

 Angleton, Tex., Sacaton, Ariz., and 

 probably at other points. Established 

 on James Island, S. C. It propagates 

 by creeping rhizomes. 



168. ZfiA L. 



Spikelets unisexual ; staminate 

 spikelets 2-flowered, in pairs, on one 

 side of a continuous rachis, one nearly 

 sessile, the other pedicellate; glumes 

 membranaceous, acute; lemma and 

 palea hyaline; pistillate spikelets ses- 

 sile, in pairs, consisting of 1 fertile 

 floret and 1 sterile floret, the latter 

 sometimes developed as a second 

 fertile floret; glumes broad, rounded 

 or emarginate at apex; sterile and 

 fertile lemmas hyaline, the palea 

 developed; style very long and slen- 

 der, stigmatic along both sides well 

 toward the base. Robust annual, with 

 terminal panicles (tassels) of stami- 

 nate racemes, and short-peduncled, 

 pistillate, 8- to many-rowed spikes 

 (ears) enclosed in numerous spathes 

 (husks). Type species, Zea mays. 

 Name Greek zea, or zeia, a kind of 

 grain. 



1. Zea mays L. Maize, Indian 

 corn. (Fig. 1199.) Tall robust monoe- 



cious annual, with overlapping sheaths 

 and broad, conspicuously distichous 

 blades; staminate spikelets in long 

 spikelike racemes, these numerous, 

 forming large spreading terminal pan- 

 icles; pistillate inflorescence in the 

 axils of the leaves, the spikelets in 

 8 to 16 or even as many as 30 rows 

 on a thickened, almost woody axis 

 (cob), the whole enclosed in nu- 

 merous large foliaceous bracts or 

 spathes, the long styles (silk) pro- 

 truding from the summit as a mass 

 of silky threads; grains at maturity 

 greatly exceeding the glumes. 6 

 — Maize or Indian corn is one of the 

 important economic plants of the 

 world, being cultivated for food for 

 man and domestic animals and for 

 forage. It originated 18 in America, 

 probably on the Mexican Plateau, 

 and was cultivated from prehistoric 

 times by the early races of American 

 aborigines, from Peru to middle 

 North America. Several races of 

 maize are grown in the United States, 19 

 the most important being dent, the 

 common commercial field sort, flint, 

 sweet, and pop. Pod corn (Z. mays 

 var. tunicata Larr. ex St. Hil.), 

 occasionally cultivated as a curiosity, 

 is a variety in which each kernel is 

 enveloped in the elongate glumes. A 

 variety with variegated leaves (Z. 

 mays var. japonica (Van Houtte) 

 Wood) is cultivated for ornament. 



18 For a note on the origin of maize, see Collins, 

 G. N. the origin* of maize. Jour. Wash. Acad. Sci. 

 2: 520-530. 1912. 



19 See the following publications: 



Mangelsdorf, P. C. and Reeves, R. G. the origin 



OF INDIAN CORN AND ITS RELATIVES. TeX. Agl\ Expt. 



Sta. Bul. 574 (monogr.): 1-315. 1939. Reeves, R. 

 G. and Mangelsdorf, P. C. Amer. Jour. Bot. 29: 815- 

 817. 1942. Sturtevant, E. L. varieties of corn. 

 U. S. Dept. Agr., Off. Expt, Sta. Bul. 57, 108 pp. 1899. 

 Tapley, W. T., Enzie, W. D., and Van Eseltine, 

 G. P., N. Y. State Agr. Expt, Sta. Rpt., 1934. 1934. 

 Weatherwax, Paul, morphology of the flowers 

 of zea mays. Torrey Bot. Club Bul. 43: 127-144. 



1916. DEVELOPMENT OF SPIKELETS OF ZEA MAYS. 



Torrey Bot. Club Bul. 43: 483-496. 1917; the evo- 

 lution of maize. Torrey Bot. Club Bul. 45: 309-342. 

 1918; the story of the maize plant. 247 pp. illus. 

 Chicago, 111., 1923; the phylogeny of zea mays. 

 Amer. Midi. Nat. 16: 1-71. 1935. 



