BETTER PLANTS AND ANIMALS 17 



2. One fourth are ^vrinkled seeds and grow into plants that 

 produce wrinkled seeds that come true. 



3. One half are smooth seeds and grow into plants that 

 produce seeds of which one fourth are wrinkled and three 

 fourths are smooth. 



18. Producing new characters by crossing. Two white- 

 flowered sweet peas of the same variety were crossed. These 

 resembled each other in all respects, except that one plant bore 

 flowers with long pollen grains, and the other bore flowers with 



FIG. ii. Polled and horned cattle 

 When polled and horned cattle are crossed, the first generation is polled 



round pollen grains. The hybrid bore purple flowers, a totally 

 new character. One of these hybrid plants bearing purple 

 flowers was crossed with another like itself. Of the offspring 

 of this cross twenty-seven plants bore purple flowers, nine bore 

 red flowers, and twenty-eight bore white flowers. Not only did 

 the purple character persist but the new character, red, appeared. 

 The limits of production of new characters by crossing are not 

 known, and a great deal of experimentation is being done on 

 this phase of the question. 



19. Character present or absent. It has recently been dis- 

 covered that there are not two opposing characters, as was at 



