292 



ELEMENTS OF GENERAL SCIENCE 



the best types of corn for the different needs of agriculture 

 and other industries, careful studies were made to determine 

 the percentage of oil and of protein substances in corn. 



It was found that in some of the ears the percentage of 

 protein was as high as 12.54 per cent, while in other ears it 

 was as low as 8.96 per cent. Likewise the oil content ranged 

 from 5.39 per cent to 4.03 per cent. 



319. Hybrids. One of the best breeds of cattle for the 

 beef-producing sections of the United States is the Hereford 



FIG. 134. Hereford cows 

 One of the breeds of domesticated cattle. Photograph by Robert K. Nabours 



(fig. 134). In some parts of the country Herefords and other 

 breeds of cattle have been seriously affected by a disease car- 

 ried by the cattle tick, and the cattle industry has suffered 

 greatly from this cause (sect. 115). The zebu, or Brahman 

 bull, of India (fig. 135) is immune to the tick and is thus free 

 from the disease which the tick carries. The zebu is not ordi- 

 narily regarded as being as good for beef production as our 

 native cattle. It occurred to certain cattle growers to produce 



