552 GLOSSARY 



Crossing. Hybridizing, or transferring pollen to the stigmas of 



a different plant, variety, or species. 

 Crown. That part of certain plants, as grains and grasses, from 



which a number of stems spring. 

 Crude fiber. The woody portion of plants. 

 Culms. Stems or erect branches. 

 Current cross. Immediate hybridization, as shown in the hybrid 



seeds developed in the same season in which impregnation 



occurs. 

 Cylas formicarius. The scientific name of the sweet-potato 



root-borer. 



Delinters. Used on p. 383 for establishments, such as cotton-oil 

 mills, which delint cotton seed, that is, subject them to a 

 second ginning. 



Delta Region. A region in the western part of Mississippi, con- 

 sisting of rich river bottom land. 



Diabrotica 12-punctata. The scientific name of the bud worm, 

 an insect attacking the stem of very young corn plants. 



Dibble. A small implement or sharpened stick for making holes 

 in the ground. 



Diplodia. The name of a genus of fungi causing some of the 

 rotting of corn ears. 



Diplosis sorghicola. The scientific name of the minute insect 

 which destroys the seeds of the sorghums, and which is 

 largely responsible for the failure of the crop of sorghum 

 seed in the humid regions of the South. 



Disinfection. Destruction of the germs of disease, usually by 

 treatment with chemicals or with heat. 



Disked. Tilled with a disk-plow or disk-harrow. 



Disk-harrow. A harrow consisting of a number of circular con- 

 cave disks. 



Disk-plow. A plow in which the work of cutting and inverting 

 the soil is done by a large, concave, circular disk which re- 

 volves. The supporting framework for the disk is shown 

 in Fig. 80. 



Dolochonyx oryzivorus. The scientific name of the rice bird or 

 bobolink. 



Dominant quality. That one of a pair of contrasted qualities which 

 shows in the larger proportion of the offspring. See p. 143. 



Double fertilization. That process occurring in the impregna- 

 tion of some plants by which the pollen influences not only 

 the germ of the seed, but also the endosperm. 



Dough stage. The stage of a maturing grain when the seed is 

 in the stage of firmness represented by dough. 



Ducts. The channels through which the crude sap of plants 

 circulates. 



