8 GRASSES OF IOWA. 



joint of an obliquely articulate rachis of a simple spike; the spikes fascicu- 

 late in the leaf axils and each more or less enveloped in a foliaceous bract. 

 Glumes of the staminate spikelets 4, acute, the first two membrana- 

 ceous, empty ; flowering glumes smaller and like their paleas, hyaline, 

 stamens 3. Glumes of the pistillate spikelets 4, the outer one broad 

 and boat-shaped, smooth, soon becoming very hard, surrounding the 

 inner glumes and narrow rachis, second glume coriaceous, third glume 

 hyaline with a palea but no flower; fourth or flowering glume and its 

 palea hyaline. Styles very long, filiform, shortly bifid at the apex. 



Tall annuals with long and broad leaves, closely resembling In- 

 dian corn in habit. Species I with several varieties in Mexico and Cen- 

 tral America. Frequently cultivated in the southern states, and occa- 

 sionally in Iowa for soiling purposes. 



2 ZEA. 



Zea. L. Sp. PI. 971. 1753. Endlicher. Gen. PI. 80. Hackel in 

 Engler and Prantl. Nat. Pflanz Fam II. 2: 19. Benth. & Hook Gen. PI. 3: 

 11.4. Scribner, Bull. U. S Dept. Agrl. Div. Agros. 20:12. f. 2. 



DESCRIPTION. 



Maize. Spikelets unisexual, monoecious; the staminate two- 

 flowered, in pairs, one sessile, the other pedicellate, arranged in terminal 

 branches of a terminal panicle ; the pistillate one-flowered, sessile, 

 crowded in several rows, along the much thickened continuous axis 

 arising from the lower leaf-axil and closely enveloped by numerous 

 large foliaceous bracts. Glumes 4, awnless ; those • of the staminate 

 spikelet acute; those of the pistillate very broad and obtuse or emarginate. 

 Grain hard, only partially enclosed by the fruiting glumes. A well- 

 known tall and striking annual grass with erect stems and broad 

 leaves. The terminal staminate inflorescence forms the "spindle" and 

 the long projecting styles of the pistillate flowers constitute the "silk." 

 The cob is formed by the union of the axes of several female spikes into 

 a much thickened body. 



Dr. E. L. Sturtevant, 1 who more than any one else has studied 

 maize in our country, regards the genus as monotypic and only recog- 

 nizes the Zea mays. 



Species 1 or 2, of American origin, presenting many varieties in 

 cultivation known as corn, Indian corn or maize. 



See Bull. 1. la. Geol. Survey, p. *43. 

 Bull. U. S. Dept. Agrl. of Exp. Sta. 57: 7. 



