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MUTATIONS 



Cattle originally had long horns. There appeared a mutant without horns. This animal 

 became the ancestor of a hornless race of cattle. 



breeds true to its type. In Paraguay in 1770, there was born a 

 hornless calf in a herd of ordinary long-horned cattle. Animals 

 without horns are less dangerous to the other animals of the herd 

 and also to their owners. Therefore, this animal was later bred 

 with the ordinary cattle and it was found that the hornlessness 

 was inherited as a dominant factor. Before this, cattle had some- 

 times been de-horned, polled artificially, but from this one animal 

 an entire race of hornless or naturally polled cattle was developed. 

 The original hornless calf was a mutant. 



Short-legged sheep, which cannot jump walls, have been devel- 

 oped from the long-legged Ancon sheep. Six fingers instead of 

 five, two joints in the fingers instead of three, and webbed 

 fingers are a few of the inherited modifications, mutations, that 

 have been found in human beings. The navel orange (seedless 

 orange) originated as a mutant in Brazil. 



The first person to use the term mutation was Professor Hugo 

 de Vries of Holland. He was born in 1848 and was, for a long time, 

 a professor at the University of Amsterdam, Holland. He carefully 

 watched the descendants of one primrose plant for several genera- 

 tions and found that it gave rise to seven distinct new species, each 

 of which bred true. Each mutant differed decidedly from the 

 others in height, shape of leaves, or some other character. 



Mutations are inheritable and there is little doubt that thev are 



