48 



THE CEREALS IN AMERICA 



of the rachi forms the cob. It is interesting to observe that 

 the development of the cob seems to be in some measure de 



pendent upon the develop- 

 ment of the grains. As the 

 tip of the cob develops last, 

 ears are likely to be more 

 tapering where soil or sea- 

 sonal conditions have been 

 unfavorable. A tapering ear 

 may, therefore, in some in- 

 Thirtyrows. Eight rows. g^ances, indicate a lack of 



adaptation to the locality in which it is grown.^ 



In the cultivated varieties the glumes and paleae are reduced 

 to small membranous parts around the base of the grains. In 

 the pod maize, however, the glumes are very large, completely 

 enclosing the grains. 



The several rachi which make up the cob usually grow nearly 

 straight from butt to tip ; hence the two-ranked spikelets result 

 in grains being usually arranged in regular order. These pairs 

 of ovularies are fertilized with such certainty that under normal 

 conditions an odd number of rows never results. Even where 

 the number of rows is less at the tip end than at the butt, the 

 number of rows remains even, — the reduction in number is made 

 by the omission of a piece of the rachis. The case of an ear 

 having twenty-one rows has been reported,^ but if authentic, is 

 certainly a very rare instance. 



218. The Position of the Ear. — The position of the ear on 

 the culm (stalk) varies more widely than does the ratio of grain 

 to stover. In some varieties the ears may be too high or too 

 low to be easily husked. When too high, the stalks are more 

 easily blown down. Four feet above ground is a desirable 

 height for ears of medium sized varieties. The shank by which 



I Torrey BuL 21, No. 12 (1894), p. 514. 



$ Trans. Mass. Soc. Prom. Agr. 1S58, p. 114 



