10 



THE VEGETABLES OF NEW YORK 



There are about seven species of this genus, all 

 American. Gama grass itself, T. dactyloides, L., has 

 the widest range of the species found in the United 

 States, occurring from Connecticut to Florida and 

 Texas. Concerning its relationship with maize, Weather- 

 wax 1 says, " The clearest and most reasonable deduction 

 from the facts at hand is that Zea, Euchlaena, and 

 Tripsacum descended directly and independently, in so 

 far as hybridization is concerned, from a common 

 ancestor now extinct." Maize has produced hybrids 

 with Tripsacum when the pollen of the latter was used 

 on silks of Maize. The reciprocal cross has not been 

 successful. Mangelsdorf and Reeves'-' of the Texas 

 Experiment Station have written an interesting account 

 of their difficulties in procuring a few fertile seeds of 

 this cross. 



5. EUCHLAENA Schrad. Jnd. Sem. Hort. 

 Goer r. 1832. — Teosinte. 



Annual or perennial grasses with unisexual spikelets; the 

 staminate spikelets similar to those of Zea: the pistillate somewhat 

 similar to those of Tripsacum, but in separate spikes enclosed in 

 husks, single, sunken in cavities on opposite sides of a jointed rachis, 

 the hardened first glume covering the cavity; second glume mem- 

 branaceous, lemmas hyaline; 2 to several pistillate spikes enclosed 

 in a single leaf sheath. 



There are two species of teosinte, the perennial, 

 E. perennis Hitchc, and the annual, E. mexicana 

 Schrad. This latter has two forms, the Floridan and 

 the Mexican. Numerous crosses of E. mexicana and 

 maize have been made and are fertile. Very few crosses 

 have been made between maize and perennial teosinte. 

 These are nearly all sterile. It has been suggested that 

 annual teosinte may have arisen from a cross between 

 perennial teosinte and maize, but proof is not forth- 

 coming as yet. 



6. ZEA L. Sp. PL 971. 1753.— Maize.— Mow 

 Adans. Fam. 2:39. 1763. Mays. Gaertn. Frucr. 

 et Sem. 1:6. 1788. Mayzea Raf. Med. Fl. 2:241. 

 1830. Thalysia Kuntze, Rev. Gen. 2:794. 1891. 



Annual grass with unisexual spikelets, the staminate ones, 

 2-flowered, in pairs, one of each pair nearly sessile, the other pedi- 

 celled; glumes membranaceous; lemma and palea hyaline; pistillate 

 spikelets sessile, in pairs, consisting of one fertile and one sterile 

 floret, or occasionally of two fertile florets; glumes broad and rounded 

 or emarginate at apex; style very long and slender. 



Only one species, Zea Mays L., is known. It is 

 discussed in detail in the following paragraphs. Unfor- 

 tunately, many of the earlier investigators thought that 

 every variation in the plants should have a scientific 

 name, and consequently, a very abundant synonomy 

 grew up. These names, placed in groups as nearly as 

 can be determined on the basis of the often meagre 

 descriptions, are given at the end of this chapter. 



The corn plant in general structure is like other 

 grasses with some interesting differences in a few details. 

 The roots like those of other grasses are fibrous, never 

 very large in diameter but often up to 5 or 6 feet in 

 length. The first rootlet from the germinating seed 

 is soon supplemented by two or three secondary roots 



from the first node of the stem and these, too, soon lose 

 their importance as longer and larger roots arise from 

 successively higher nodes. As the plant begins to 

 develop its greatest growth, brace, prop, or buttress roots 

 usually begin to appear from the first few nodes above 

 the ground level. These are thicker and stronger than 

 the roots produced below ground level but otherwise 

 have the same structure. They vary in different 

 strains of corn. 



The stem consists of a series of sections divided by 

 swollen portions or nodes. The intervening portions, 

 internodes, between each pair of nodes bear a leaf at the 

 upper end and a bud or at least bud tissues, at the lower 

 end. This bud may or may not develop into a branch. 

 The internodes are filled with pith as in the Andro- 

 pogoneae, but unlike those of most other grasses which 

 are generally hollow. The growth of the internodes 

 is similar, however, there being some capacity for 

 increase in thickness in very young internodes and 

 always capacity for increasing in length from the grow- 

 ing region at the base of each internode. The growth in 

 length ordinarily slows up and gradually ceases as the 

 plant matures but may continue if the plant is blown 

 over by the wind or thrown on the ground by other 

 accidents. 



The leaf of maize like that of most other grasses 

 shows three distinct portions. The first portion is a 

 cylindrical sheath split down one side and with edges 

 more or less overlapping throughout its length. This 

 split often does not open until above the second node. 

 It has been suggested that the sheath is homologous 

 to the swollen base of the leaf stalks of the maple, for 

 instance. In any case it serves to strengthen the stem 

 and to protect the growing region of the next higher 

 internode. The second portion is a long, flat, strap- 

 shaped blade with a strong midrib and numerous smaller 

 veins parallel to it. The blade tapers to a point at the 

 tip and is more or less heart-shaped at the base where 

 it meets the sheath, having generally a distinct lobe or 

 auricle at each side. The third portion is a thin mem- 

 branaceous collar, the ligule, which arises at the upper 

 side of the juncture of the sheath and blade. It fits 

 closely about the next internode thus protecting the 

 latter from water, dust, and spores. The leaves are 

 arranged in two ranks. 



The buds on the lower internodes may develop 

 large branches, suckers, or tillers, similar to the main 

 stem, while one or more of those of the middle inter- 

 nodes produce short ear-bearing branches. The buds 

 of the upper nodes may grow into small branches often 

 not attaining the length of the enveloping sheath or 

 may remain entirely dormant. 



The terminal section of the main stem (and some- 

 times those of the suckers or tillers) develops into a 

 staminate inflorescence or tassel, while the terminal 

 section of some of the short middle branches develops 

 into pistillate inflorescences or ears. 



The tassel differs radically from the main stem below 



1 Weatherwax, Paul. Loc. cit. 30. 



'■ Mangelsdorf, P. C, and Reeves, R. G. 



Hybridization of Maize, Tripsacum, and Euchlaena. Jour. Heredity. 22:329 {{. 1931. 





