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ELEMENTS OF GENERAL SCIENCE 



offspring might possess the desirable beef qualities of the 

 Hereford with the tick immunity of the zebu. As a result 

 of this experiment offspring were produced (fig. 180) showing 

 various characteristics of the two kinds of parents. Offspring 

 produced by crossbreeding are known as hybrids. 



Some of the cattle produced as a result of the experiment 

 jnst cited resemble the Hereford, some resemble the zebu, 



FIG. 178. Hereford cows 

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



and some bear partial resemblance to both parents. Some of 

 the offspring retain the bodily form of the Hereford and the 

 zebu's immunity to the cattle tick. Those individuals which 

 retain these qualities are now being used as parents for the 

 production of other cattle, with the hope that this new breed 

 will retain the desired qualities. If this can be accomplished 

 it will give us the solution of an important practical problem. 

 Among plants and animals many hybrids are constantly 

 being produced. Hybridization presents an important method 

 of production of variations. 



