458 Plant-Breeding 



periment stations, or from nurserymen or growers, samples of 

 citrus hybrids, such as citranges, tangelos, and the like, and 

 samples of Citrus trifoliata. Purchase oranges, lemons, grape- 

 fruits, and tangerines from the fruit stores. Provide also for 

 each student, or group of students, a glass, spoon, sugar, and 

 water. 



Compare the hybrids with their parents, with special reference 

 to the following points : - 



(a) Fruit size, shape, color, amount of juice, quality of 

 juice, condition of segments, etc. 



(6) Trees (if branches or photos are available) size, shape, 

 branching, kind of leaves, etc. 



(c) General length of season, resistance to cold, etc. 



Squeeze out the juice from several fruits, add sugar and water, 

 and test the adaptability for beverage and other economic 

 purposes. 



EXERCISE 24 



Study of the Results of the Plant-to-Row Tests of Wheat, Oats, 

 Cabbage, Onions, or any Crop where Data are Available 



EXERCISE 25 



Studies of Origin of Varieties Corn, Wheat, Apples, Plums, 



Grapes, Etc. 



Literature study of the history of varieties. Methods em- 

 ployed to originate varieties should be carefully noted. 



EXERCISE 26 



Field Trip to Experimental Grounds 



Most experiment stations have plant-breeding experiments 

 under way, and if a fall inspection of the plats would be in- 

 structive to students, they should be taken on such a trip early 



