ZEA 



from the Teosinte (Euchhvna Mexicana), a fodder 

 grass that is much grown in Mexico. See Teosinte. 

 This latter view has arisen from experiments in cross- 

 ing Teosinte and Maize, whe.reby a maize-like plant has 

 been produced, thus showing the very close affinity of 

 the two species. Plants of this hybrid were thought by 

 the late Sereno Watson and others to constitute a new 

 species of Zea, and Watson named it Z. canina. This 

 plant quickly reverts to ordinary Corn when grown in 

 the North (see Harshherger, G. P. 9:522; Contr. Bot. 

 Lab. Univ. Penn. 2:231. Also Bailey, Bull. 49, Cornell 

 Exp. Sta.). Figs. 2774, 2775. Zea Mays, therefore, may 

 be (1) a true species, of which the wild prototype is 

 unknown; (2) a direct offshoot by domestication of 

 Euchhtna Mexicana; (3) a product of crossing between 

 Euchlcena Mexicana and some unknown related species; 

 (4) a product of crossing between Suehlana Mexicana 

 and a domesticated race of the same species. Our 

 knowledge is yet insufficient to enable us to offer much 

 more than conjecture on these categories. 



Maize is remarkably variable, although most of the 

 variations intergrade in different regions and under 

 different conditions. The most extended American study 

 of variation and varieties in Maize has been made by 

 the late Dr. E. Lewis Sturtevant. The summary of his 

 study of varieties is published as Bull. 57, Office of 

 Experiment Stations, U. S. Dept. of Agric. ("Varieties 

 of Corn," 1899). Sturtevant throws the varieties of 

 Maize into seven "species groups" or "agricultural 

 species." The distinguishing characters of these 

 groups are founded on the kernels. Aside from these 

 there is at least one well-marked race 

 of ornamental maize, Zea Japonica, 

 which for horticultural purposes may 

 well be separated from the others. In 

 the following classification, the char- 

 acters of the races, except of the orna- (f i l SJS|I 

 mental sorts, are copied from Sturte- i\%' V..,i 

 vant. It is probable that a strict in- 'f fi-'l ' ^4 



ZEA 



2005 



2775. Ear of Zea 

 canina, second 

 year from the 

 wild. Cob flat- 

 tish(X%). 



quiry into the no- 

 menclature of Zea 

 Mays would find 

 other names to re- 

 place some of those 

 given by Sturte- 

 vant; but his 

 names have the 

 great merits of defi- 

 niteness and of ap- 

 plicability to Amer- 

 ican forms of 

 Maize. 



Zea Mays, Linn. Maize. Indian Corn. A com- 

 posite species, of which no single form can be taken as 

 the type. Linnaeus meant the name to cover the whole 

 range of forms then grown in European gardens. 

 Tender annual. If an original specific form of Maize 

 were to be discovered, this form would no doubt be 



2774. Zea canina, showine the lone 

 branches, with ears at the joints. 



taken as the type, and all other forms ranged as varie- 

 ties of it. 



A. Maize grown for ornament. 



Var. Jap6nica, Koern. (Z. Jap6nica, Van Houtte. 

 Z. vitt&ta, Hort.). Foliage variously striped with 

 white: plant small. Said to have come from Japan. 

 F.S. 16:1673-4. Ears small; kernels yellowish, flint. 



Var. gracillima, Koern. (Z. gracillima and Z. minima, 

 Hort. }. Very dwarf, slender form with green lvs., some- 

 times cult, in Eu. A 

 variety variegata is also 

 mentioned. 



Var. Curagua, Alef. 

 (Z. Curdgua y Molina), 

 is described as a very 

 robust green - leaved 

 form. Sturtevant places 

 it in the Pop Corn tribe. 

 Gn. 42, p. 207. 



2776. Zea canina, third 

 year from the wild. 

 Kernels less pointed. 

 Cob nearly cylindrical 



2777. Pod or Husk Corn. -Zea 

 Mays, var. tunicata (X %). 



Each kernel inclosed in a husk. 



AA. Maize grown primarily 



for the grain or fruit. 



Var. tunicata (Z, tnnicata t 



Sturt.). Pod Corn. Figs. 2777, 



2778. Plate VII. In this group 

 each kernel is inclosed in a 

 pod or husk, and the ear thus 

 formed is inclosed in husks. 



Var. everta (Z. evtvta, 

 Sturt.). Pop Corn. Fig. 551, 

 Vol. I. Plate VII. This group is characterized by the 

 excessive proportion of the corneous endosperm and the 

 small size of the kernels and ear. The best varieties 

 have a corneous endosperm throughout. This gives the 

 property of popping, which is the complete eversion or 

 turning inside out of the kernel through the explosion 

 of the contained moisture on application of heat. A 

 small deposit of starchy endosperm does not greatly in- 

 terfere with this property of popping, but when the 

 starchy endosperm is in excess, as in a flint Corn, the 

 kernel does not evert, but the corneous portion only ex- 

 plodes or splits, leaving the starchy portion unchanged. 

 The true Pop Corn is hence 

 tender in its eating; the 

 false Pop Corn has a ten- 

 der portion of limited ex- 

 tent only. This class of 

 Corns is even more readily 

 recognized by inspection 

 than by description. 



Var. indurata (Z. in- 

 durata, Sturt.). Flint 

 Corn. Plate VII. Fig. 

 ?779. A group readily re- 

 cognized by the occurrence 

 of a starchy endosperm, 

 inclosed in a corneous en- 

 dosperm, as shown in a 

 split seed. This corneous 

 endosperm varies in thickness with varieties. When 

 very thin at the summit of the kernel the shrinkage of 

 the starchy endosperm may cause a depression, thus 

 simulating externally a dent from which its structure 

 at once differentiates it. 



2778. Cross-section of ear i 

 Husk Corn (X %). 



