PLANT HYBRIDIZATION BEFORE MENDEL 117 



heterogeneous mass, when between one and two hundred sets have been 

 grown within a foot of each other for nearly fourteen years." 



ShirrefF remarks pointedly upon the necessity for the final test 

 of the product, as the criterion of science In the improvement of 

 wheat. 



"One of the chief difficulties which an individual experiences when 

 improving the plant, is to ascertain the quality of the grain or the flour 

 produced from it. . . . In an inquiry of this nature, the aid of the 

 chemist is thought to be of little avail, and the baker's bread, taking 

 color, quality, and quantity into consideration, is a more satisfactory 

 test to the farmer." (p. 62.) 



"In carrying out the improvement of cereals, the selecting of varieties 

 may be considered an important step; and the object in all probability, 

 will be sooner accomplished and better controlled, by first creating a 

 diversity, which can easily be effected by crossing. . . . Crossing tends 

 to produce variation in kinds not given to sporting, and in this respect 

 it has much advantage over the system of improvement by merely select- 

 ing from the crops of the farm. A new and important source of varia- 

 tion is opened up by crossing, but a judicious improver of the cereals 

 will never overlook this interesting proceeding. Always cross with the 

 seedlings which inherit in the greatest degree the properties you wish 

 a cereal to possess, and by persevering for a series of years to select, 

 and by crossing in this manner, success in all probability will be ulti- 

 mately attained." (p. 95.) 



BIBLIOGRAPHY 



1. Goss, John. 



On the variation in the color of peas, occasioned by cross- 

 impregnation. Transactions of the Horticultural Society of 

 London, 5:234, 1824. 



2. Herbert, William. 



(a) On the production of hybrid vegetables, with the result 

 of many experiments made 4n the investigation of the 

 subject. Transactions, Horticultural Society of London, 

 4:15-50, 1819. 



(b) On crosses and hybrid intermixtures in vegetables, pp. 

 335-80 fat end of 2c). 



(c) Amaryllidaceae ; preceded by an attempt to arrange the 

 Monocotyledonous orders, and followed by a treatise 



